Forget "PC vs Console" wars. Now it's going to be "iPad vs Mac". (Keyboard and mouse forever!)
Guerilla Bob is a simplistic, three-quarters-overhead shooter in the Ikari Warriors vein, but that's not what makes it unique. It's that the co-op shoot 'em up doesn't just allow two iOS devices to team up, but supports full compatibility between the OS X version as well.
We fired up a copy of the Mac version ($5 on the Mac App Store), hosted a game, and soon had an iPad 2 shooting right alongside my iMac here in the office. Graphically, except for the much higher resolution of the iMac version, they were pretty much identical.
Which makes that $.99 cent price of the iOS version a much better buy.