hmm....there were LOTS of Doom maps...lots of QUAKE maps....lots of HL maps...
I think having an "easy" to use level editor is great. It will mean lots of people will create content, and then there will be more demand for content aggregation/review sites that help us find good stuff from the not so good stuff.
At first, everything may indeed look like what's already in the Crysis game. But that was the case with Doom and Quake and Half-Life. And at first, assuming if Crysis the game is excellent enough, we'll all be happy to play more of what we just got. As time goes by and people figure out how to really use everything, some total conversions and kickass mods will come out...you know how the story goes.
Biggest question is how easy it is to integrate everything. Certainly Source engine left the window open in that department.
edit...
I'm trying to understand...do people feel a bit threatened by a potentially easy to use level editor? Just because it is easy to use, it doesn't mean suddenly someone is going to learn it and make better content then you. That brings up the question of what's more important: your technical skills/experience at using tools or your ability to imagine better gameplay, design and art content?
I predict that if Crysis is really that easy (we'll see once it goes to John Q Public!) it will end up being a good thing, despite having to wade through tons of crap levels that will ensue!