The more I see about LEGO Universe, the more I want to play this game. So we saw this a bit in previews, but there are 3 tiers of building in the game.
There is the quick build from the console LEGO games.
Then there is a modular build, where you have choices of what pieces to use for each section, allowing you to have a custom item.
Finally, is an analog type build type, which is almost like playing LEGO in the virtual world. You do it in your own "chunk" of land, meaning you can build your own castle, wild west fort, or any other number of things.
So not only do they have their own content that they are pushing out, but the players will be making content for others to explore.
I'm pretty sure that this is a game that will not only be profitable, but that it will last for years and years to come. I know that the adventure side will probably be really light for MMO veterans, but the free build mode, will attract people of ALL ages.