2 Hour Auctions are definitely too long. If they functioned like an eBay auction, they'd be fine. But as implemented they are just annoying. Even joining one, means that I have to know I'll be near a computer, and free 2 hours later if it's something worth bidding on. And I routinely forget to check back in time.
I wish I could set a max bid, that wasn't immediately the new price, like any other online auction marketplace. I would participate FAR more, if I could set a max price without it being my actual immediate bid.