So many of us, including myself love shiny graphics, but don't have beast rigs to handle them! This list will give you the necessary links and mods to download to make Oblivion look good, and perform well on a mid range rig. Check these screens out:

http://tesalliance.org/forums/index.php?/gallery/image/15656-screenshot2jpg/
http://tesalliance.org/forums/index.php?/gallery/image/15662-screenshot8jpg/
http://tesalliance.org/forums/index.php?/gallery/image/15661-screenshot7jpg/

Not bad eh? Those were taken using an ATI Radeon HD 5470, which is by no means a strong card, just a mid range card

So lets begin! Download and install in the order listed.

Step One: GFX Card Tweaks
This step really helps out. Using these tweaks you can force some real good looking graphics into your game with only a minor performance hit.
1) Open your GFX card panel properties
2) Move Anti-Aliasing up to 4x (The highest your card allows)
3) Move Anisotrophic Filtering up to 16x (The highest your card allows)
4) Set Mip mapping to performance (This gives you some mip mapping with out a gigantic performance hit)

Step Two: World Textures and Replacers
The textures are the most important part of this list. Replacers are also important, but the textures are what will make this look good for ya.
1) Download and install http://www.tesnexus.com/downloads/file.php?id=37336, as well as its http://www.tesnexus.com/downloads/file.php?id=38658. This can be interchanged with other texture replacers, such as Corepc's textures, but this is my personal favorite. It works well and gives good performance since the textures are only 512x512 in size, the size of standard vanilla textures
2) This is the most imperitive download. Download and install http://www.tesnexus.com/downloads/file.php?id=38204. These normal maps adds huge amounts of detail to the game, and give the good "bumpy" feeling you see in my screens.
3) Download and install http://tesalliance.org/forums/index.php?/files/file/903-beta-insanitys-imperial-city/. This texture pack is the only other architecture texture pack I will recommend to download. The Imperial City contains a lot of low res textures that cant be fixed through normal maps or higher anisotrophic filtering, and IS's wonderful high res retextures here are the best IMO.
4) Download and install http://tesalliance.org/forums/index.php?/files/file/726-snow-texture-replacer/.
5) Download and install http://www.tesnexus.com/downloads/file.php?id=34175.

Step Three: Body Replacers and Race Additions
Lets face it. Oblivion's default body is just hideous! Following these steps we can make them much more purty! Many things wont be linked due to graphic content.
1) Download and Install Roberts Male Body v5, as well as the stock clothing and armor replacer.
2) Download a female body replacer of your choice. There is ALOT of them, so look around and make your pick. I'm using HGEC myself, with its stock clothing and armor replacer.
3) If using HGEC download and install Ozmo's high rez skin textures
4) If using HGEC download and install http://www.tesnexus.com/downloads/file.php?id=35501.
5) Download and install http://www.tesnexus.com/downloads/file.php?id=11954.
6) Download and install http://www.tesnexus.com/downloads/file.php?id=33396, http://www.tesnexus.com/downloads/file.php?id=35202, http://www.tesnexus.com/downloads/file.php?id=13331, http://www.tesnexus.com/downloads/file.php?id=13602 and http://planetelderscrolls.gamespy.com/View.php?id=3309&view=OblivionMods.Detail.
7) Download and install Slof's Oblivion Beasts Improved. It adds claws and spikes to the Argonians and whiskers and nails to the Khajiit.
Thats all I have installed, but look around there is tons of other replacers out there, some you may like more than these XD

Step Four: General Replacers and Improvers
We all know that somethings in Oblivion just look plain low res.... and awful. These replacers should help to cure that XD
1) Download and install http://www.tesnexus.com/downloads/file.php?id=30555.
2) Download and install http://www.tesnexus.com/downloads/file.php?id=31337.
3) Download and Install http://www.tesnexus.com/downloads/file.php?id=27882.
4) Download and install http://www.tesnexus.com/downloads/file.php?id=20001.
5) Download and Install http://www.tesnexus.com/downloads/file.php?id=15999.
6) Download and install http://www.tesnexus.com/downloads/file.php?id=9746.
7) Download and install http://www.tesnexus.com/downloads/file.php?id=9498.
8) Download and install http://www.tesnexus.com/downloads/file.php?id=27138.
9) Download and install http://tesalliance.org/forums/index.php?/files/file/871-necromancer-banner-replacer/.
10) Download and install http://www.tesnexus.com/downloads/file.php?id=38061.
11) Download and install http://www.tesnexus.com/downloads/file.php?id=36075.
12) Download and install http://www.tesnexus.com/downloads/file.php?id=18579.
13) Download and install http://www.tesnexus.com/downloads/file.php?id=25314. Install this after Improved Signs. Thanks to Greenie for this suggestion!

Step Five: Critters
Yes we do need to something about the bestiary. Sure everyone of them wants to kill ya, but that dont mean they can't look good!
1) Download and install ALL of http://www.tesnexus.com/modules/members/index.php?id=610829. His are the best out there, be sure to download at the highest res possible. Don't worry it wont kill your frames!
2) Download and install Slof's Horse's. Sorry I cant find a link at the minute, but search around it should be around. These horse textures are just awesome!

Step Six: Weapons and Armor
One modder made a whole ton of high res replacements for the vanilla weapons and armor. I think you can guess who that is (IS).
1) Download and install all of http://www.gamesas.com/index.php?/topic/1179485-relz-insanitys-retexture-releases. High res vanilla weapons and armor for everyone! I'd link ya but that would take a heck of a long time so just follow the links in his thread! Everything there is a must for your install XD

There ya have it, don't think I forgot anything so enjoy! You'll notice alot of textures haven't been replaced with this list. The trick here is Really Textured Normal Maps. It gives the detail high res textures do with the performance hit. So now that you've done everything on this list what are ya waiting for? Get playing!

I call sticky! I also highly recommend Alien Slof's Better Bodies(not Better beasts). It's a wonderful addition especially for Robert Male users (HGEC not so much). It adds a lot of cool tattoos that fit all the races along with body hair depending on the race. It's really well done and very immersive in game!

Seconded on the sticky. And I'd really like to use Slof's Better Bodies...but she changed the look of the Khajiits (of which my PC is one) too much for my tastes! If anyone comes out with a more vanilla-y Khajiit skin for that pack then I'm there.

I also think that Qarl's Texture Pack 3 Redimized/+Reduced could fit on the "midrange" list...so long as it isn't combined with a "Visibile When Distant" mod

Out of curiosity: When it comes to Oblivion, where would the community place my card (Nvidia GeForce 9600M GS, 1GB)? Would it be considered low-end, mid-range, high-end...? I don't want to sidetrack this conversation, so please PM me instead of posting to this topic if you want to reply.