So far F3 has given me about 20 hours of fun exploring the countryside and senselessly murdering bystanders.
However some things really annoy me.
The NPC's, dialogue and quests are by a Gabe Newell's waist-sized margin the worst things about the game... which is kinda like a V.A.T.S critical shot to the knee for game design. So far I've met maybe one or two memorable NPC's (Deputy Steele's opening line ”Kill 'em all, let God sort them out!” followed by an instant crash to desktop was hilarious) and countless number of re-hashed and ugly speaking heads.
Also Fallout 3 is waaaaaaaaaay too easy. On hard difficulty the enemies do not pose any real threat whatsoever. Struggling to survive? I'd say it's more like struggling not to yawn during battles.