For that price you are almost better off waiting for a package deal (like with the M18 chainsaw). A good deal tends to be $10 per m18 amp hour pre-tax/shipping.
The battery deals this year are definitely fewer and further between.
Yeah, that's how I got my current 12.0, is with the chainsaw purchase this spring (came with a free 8.0 too). I was thinking about adding another so I don't have to rely on the 8.0 while the 12.0 is charging.
Lots of things are few and far between these days...

