What kind of in-game purchases are there going to be?
I really hate in-game purchases, it can ruin RP and the economy.
I can see using real cash for uploading content or for a monthly subscription, but that's about it.
Here's an example, What's the point of becoming a millionaire if someone can buy in-game currency?
Or why hold a fashion show if the best looking outfits are paid with real cash?
Second-Life is a great example of a game destroyed by users making a profit.