Yeah, I noticed this as well. I was first (or at least one of the very first) to buy and review the game. I bought it thinking it'd work on iPod touch and I found out (after I had spent $10 on it) that it didn't. I reported a problem about it not being compatible with my device to get my money back.
The other day I noticed it was updated so that it'd work on iTouch. I was going to re-buy it but it said it wasn't available in the US store. I really hope they're planning on putting it back up because I really really love games like that.