7" tablets have been around, but so were mp3 players (even good ones!) when they debuted the iPod. Until the Nexus 7, I don't think there were any worth looking at.

A well built Apple branded tablet with iOS (and all the apps) for under $300 might not be technologically interesting, but it will immediately outsell everything because everyone's aunt will know exactly how it works and every app you've heard of will work with it.

ICS/JB are fantastic, but I'd predict that iOS's sheer familiarity will win out for most consumers. It's not really much of a prediction since Apple's so handily owned the 10" tablet market despite an abundance of competition.