[nat]

I assume that they have a legion of econ and psych phds who determined that this will net them more money. I'll trust their judgment on this.

This probably doesn't change optimal bidding strategy though. If the thing is worth $X to you put in a snipe for $X (don't bid early - no use in giving free information to other bidders) and forget about it. Yes, someone can top you in extended bidding, but that shouldn't change your strategy. If bidding goes above $X you're better off not buying it than you would be buying it. If it would have sold for $(X - Y) under the old system and now sells for $(X - Z) for Z < Y, then you're paying more under this system than the old one, but as long as you don't watch the auction and get suckered into bidding above $X you're still getting the item for less than (or equal to) what it's worth to you. Which means that it's still rational to place your bids.