Well for one, this is a one time payment. User content is free (although in future there is a possibility of charging (possibility)). Plus there is no way of rating user generated content on Live. There will be no why of knowing the quality of the game until you have paid for it.
Plus, do you actually believe someone will make anything anywhere near the quality/scale of LBP?
There are thousands of user generated games on the internet (PC), 99.99% of them are rubbish, the games on Live will be no different I imagine. The prospect of trolling through hundreds of games in the hopes of finding something semi interesting does not appeal to me.
Developers have expressed on countless occasions the troubles with MS restrictions. I'll take they're opinion over yours I'm afraid.
Still the headline and caption picture maybe a little far fetched.
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