It went better than I imagined.
I had too many people show up for the game, which was at testament to the popularity of Fallout and that people want to play it. I continued to work on it and while my notes are rough, they are a good enough for me to run my games with. Some of the notes won't mean much unless you are familiar with the game system I'm using, but most of it should be pretty self-explanatory.
Not being a stranger to tabletop games, I selected the game that I thought would work best for Fallout. The game had to support VATS like targeting and combat, allow for some outrageous monsters, and be gritty enough to feel like a survival game. There aren't a lot of games out there that can do that off the shelf.
I selected the Hero System as the game engine on which to build Fallout. Suffice to say it was a perfect match, providing dramatic action with just enough grit to feel deadly and threatening. The hit location and damage system used by Hero is also a near perfect fit for VATS. Players that have never played Hero before can sit down and get into the game without worrying about the rules. Obviously, the GM needs to know the rules but the players can pretty much just describe what they want to do and the system will model it.
I've run 2 5-hour adventures at 3 different cons. Everyone had a blast and it really demonstrated to me that the game is a great time when played with friends.
A really fun aspect is being able to use the Fallout Wiki as players decide what/where they are doing/going.
I've posted my conversion online: http://www.legendsmiths.com/adventures/fallout
It will make more sense if you are familiar with the Hero System.
Really, the biggest hurdle was converting the equipment. Damage was the key element - I figured out what the mapping of damage between Fallout and Hero was and then everything fell into place (my http://www.legendsmiths.com/adventures/fallout/conversion-notes are on the site). Once you have all the weapons, and armor, and chems, and such, plus rules for how they affect the characters, the rest of the work is handled by the system itself - skills, characteristics, talents, powers... all of them map very easily, often directly from Fallout/SPECIAL.
The 6 characters I use for running the adventures are posted in the http://www.legendsmiths.com/adventures/fallout/characters section.
I present http://www.legendsmiths.com/adventures/fallout/equipment as a list/DB compiled from the Wiki. The Hero System also has its own character generation tool, so I have posted a "prefab" datafile for using all of the equipment with the character generator. You can also grab a http://docs.google.com/viewer?a=v&pid=sites&srcid=bGVnZW5kc21pdGhzLmNvbXxsZWdlbmRzbWl0aHN8Z3g6NGE2Y2I3MWFkNzkxMjMyOA produced from that equipment file, with full Hero stats.
The biggest inspiration, other than Fallout itself, was the publication of https://www.herogames.com/viewItem.htm?itemID=223390 - the genre book for PA in the system. While the core rules really cover everything you need, this genre book does a great job talking about the tropes of fallout-style play and how you run that type of game.
If you want to learn more about the Hero System, I recommend you explore their website and the forums. There is also a system overview document "https://www.herogames.com/get/HRO_int.pdf" that is a good place to start.
I had thought about just running the game using SPECIAL, but when you have open-ended play that system comes up a little short. Rather than trying to creat all sorts of rules to get that working, I chose a game tha was already done and had the right feel to support Fallout. Not to mention some aspects of SPECIAL, especially in it's FO3 implementation, are a bitt too crunchy for tabletop (bonus calculations, skills, etc) - that's okay in my book. As long as the tabletop game feels like Fallout, I've got no problems.
Well, that's it. I wouldn't mind moving this conversion effort out into the community - the more people playing it the better it can become. If you have any questions, about Hero or the conversion, let me know or join the conversation in the http://www.herogames.com/forums/showthread.php/81676-Fallout-Hero-(6E) to work out some of the details.
Enjoy.