To quote RichieJr of PS3Trophies (linked above):

Fallout 3 Trophies are out! And a lot sooner than most of you were expecting too! The 1.10 patch is now available for download, so you can start earning those sweet, sweet trophies. Now most of you can actually play the game instead of waiting for trophies

For the full trophy list, check http://www.ps3trophies.co.uk/trophy.php?forumid=134.

Thanks to MizuhoChan for first discovering the patch.

Note: It seems that the patch isn't available in a lot of areas. We're not sure why some of you can get it and some of you can't, all we can say is you're extremely lucky if you've got it. Hopefully it won't be too long before trophies are out for all. More PlayStation 3 News...