My (Bluetooth) Wireless Mighty Mouse started acting up a bit. The scroll button quit scrolling up. Scrolling down and scrolling left and right worked as always. Annoying to have to use the screen scroll bar as in days of yore. Anyway, it was off to the Apple store. It's less than 4 miles away from the house (and how convenient is that? :) )
The red shirt, apparently the sales team uniform today, was not very helpful. "Oh, that's a support item. You'll have to make an appointment. See one of hose ladies in turquoise shirts."
Turquoise shirt was much better. "Ah, yes the scrolling issues. And you haven't even had it long!" She grabbed a new mouse off the shelf, scanned the barcodes on the original sales receipts and the old and new mouse boxes and off I went. She e-mailed me the zero balance receipt. Now, that I like!
It appears to me the Mighty Mouse scroll has a design or manufacturing flaw of some kind.