will stay at 5mp sensor. Photography isn't that important on iPad than it is on the iPhone. Apple will continue with the 5MP iSight camera slightly tweaking it instead jump to the 8MP shooter on the iPhone 5 or 5c or the improved iPhone 5s camera. Apple will choose 8mp for iPad, when iPhone 6 gets 12mp or 13mp sensor.
It does not make sense iPad and iPhone has same MP of camera sensor. That eats their profits.
I think the big innovation that Apple hypes in the iPad 5 will be a 64 bit A7 processor. Apple is indeed under pressure to keep costs down in the new iPads. According to a recent report by market researcher IDC, Apple iPads dropped from a 60.3% share of worldwide tablets to 32.5% share in one year's times.