Currently finished just 13 quests, killed about 700 both creature and human, and 63 locations discovered. Yup currently i am exploring the map more often than taking on quest.
The early dozen quests didn't impress me much and pretty similar to previous Bethesda games. There should be more interesting story attached to the quests. Unfortunately as in current state, Fallout 3 doesn't has good writing/dialogue and story. I don't even see a descriptions on weapons and tons of other items that scattered around the game world.
The place i'm visiting now is the slaver town and it's kind of disappointing: there no exciting, long or complex quests or story here; and no memorable NPCs either. Couple kids here asked to be rescued while at the same time calling me the potential saver "mungo", "stupid", and "asshole". Strange stuff. Unfortunately so far i yet found an option to tell the slave master about the kid's plan. Also, it will be good if Bethesda introduces a companion here with story and quest, etc. But so far i don't see that coming.