In an interview with Eurogamer, Fallout 3 lead producer Jeff Gardiner reveals that the Broken Steel downloadable content due out in March allow players to take their character all the way to level 30.
Along with the promised raise in the level cap to 30, Broken Steel also removes the ending for the game, allowing players to continue on in their adventure rather than having to deal with those pesky ending credits.
"Along with removing the game's 'ending' with Broken Steel, we figure raising the level cap would allow them to [enjoy the game for longer]. We plan on raising it to level 30 - but it will be a long, hard climb to get there!"
Yes, yes, we've heard the long, hard climb statement before. Bet you $10 some European WoW guild hits 30 after the DLC is released.
Bethesda to raise Fallout level cap to 30 [Eurogamer]