I checked Wii availability today and it's as low as I've seen it in months in the U.S. Nintendo has said both that they've greatly increased inventory shipments to North America AND that they still won't meet demand.
Counterpoint: I finally saw Wii units in stock just this past Sunday. It was at the Target in Leominster, and there were at least two in the case. This is the first time I've seen a Wii for sale anywhere, save for the time I got in line at 6:30 AM to buy one. Obviously this doesn't actually mean anything, particularly because the Wii probably will be no easier to acquire this holiday season. I just thought it was fascinating that it's taken nearly 11 months before I randomly encountered a Wii. Contrast that with the Xbox 360 (five months) and the PS3 (two months). And the only reason Target had the units in stock is because most people probably aren't thinking about Christmas shopping yet.