As a modder myself I expect anything and everything and then some of the unexpected. That's what's so great about mods. There will of course be your advlt mods, UI improvements / changes, core game play changes, perk tweaks, combat tweaks, custom armor / clothing, custom companions, custom quests, custom locations.... you name it Skyrim Nexus will have it eventually.

I am a bit concerned though, like I said I am a modder myself. I know from modding for oblivion, FO:3 and FO:NV that the tool kit was largely similar due to the same engine being used. I am getting the feeling that the new creation engine is going to have an entirely new toolkit and it's going to take a lot of trial, error and time before some real quality stuff starts being produced till people get over the learning curve. Can anyone shed any light on this? Don't even get me started on the possibilities and complexity of Radiant Story

Skrim has made a lot of core changes (all for the better imo) but I get the feeling that the difficulty / skill required for modding it is going to increase sharply as a result. Once again can anyone confirm?

One last question, anyone know if the new engine still abides by the same file structure? i.e. esp's esm's bsa's, texture / mesh formats? Or are we starting back at square one on the learning curve?

My understanding is that Skyrim is using a re-written Gamebryo engine. I have some hope that we will continue to see .esps and .esms (though possibly using different names).

That would be nice though I am praying that we may be able to get some mileage out of old utilities like bsa unpackers, TES/Fo/FONVedit etc. Obviously they will all need to be updated for Skyrim with the exception of the unpackers if there are still bsa's, but if all the modding "utilities" need to be re-written from the ground up, modder's hands are going to be tied for a bit