O.K., this is how it went for me; (before I start, when the game first came out- I had multiple CTD issues/freezing, you name it, unplayable on a high end system, nothing worked, finally I got a piece of hardware traded out (hard drive but replaced with an identical - seagate barracuda, and boom, no problems, and fallout3 was the only game of many that was a problem on my system- go figure- with either hard drive), anyhow, I've noticed gfwl is a problem, (yeah yeah I know, in more ways than one!) but I have played to completion the goty prior to getting a gamertag and using Live, system ran like lightning, just like always no hiccups, nothing, -I get a gamertag and all the sudden my game is sluggish, hesitant, occassional CTD, only since Live was installed- I just narrowed it down, I was having a problem today, I am to go drain the pipes at 'dad's' request and right before I get to them, I freeze, sounds continue like nothing is wrong, but I have to get out of the game, restart, same problem, even tried running security on silent mode, no change, (so I turned it back on!), and this is the first time I've gotten this far since Live is logged in, counting achievements and so on, many times prior without Live, not one problem, I just put it to the test and Logged out of Live, pulled an old game save, went all the way through and drained the pipes, no freeze, no problem. It's Live. At least for some of the cases, my original problems when it was first bought, I didn't have Live at all, but now, it's definately Live. Perhaps that's why the problems aren't getting fixed, perhaps it's M$. No telling- just one persons explanation/fix of freezing.
P.S. I read below how one person asked how the game could get such accolades and I've been asking that since it was released. It's a great game when it runs, but with SO MANY people having such game breaking problems, well- I smell bought reviews!!