We've had the self-checkout lanes for a while here in Atlanta and I like them to a certain extent. However, it sucks when you're trying to get out of the store quickly and you have a bottle of wine or a 12-pack of beer to deal with.
You're in a hurry and the regular cashier lines are long so you go to the self-checkout aisle, but you still have to drag out your ID and walk it over to the cashier supervising the SC line. It's been my experience that most of these people are hanging out with their buddies 99.9% of the time, so you have to stand there for five minutes waiting to show your ID until Suzy gets finished telling Janey how much she's in love with the new bag boy.
Another problem with the SC is when the items don't want to scan for one reason or another, or you have a few large items that just won't fit onto the bagging table. If you move them off the table, you screw up the whole process because you've upset the little scale that's built into the machine, and then you have to go interrupt Janey again to get her to fix the problem.
As long as I'm buying small, non-alcoholic items, though, the system works great, and I move in and out of the store easily and quickly.