In true Apple fashion, I think the next iPad will be what the first one should've been (more RAM, front-facing camera).
The iPad, like the iPhone, probably won't really hit its stride until the third or fourth version. Remember how the first iPhone seemed "lacking" in various ways (no 3G, etc.) and it took another year or two for it to really "click". Same with the iPod and, to some degree, the iMac years ago (the DV models - Airport, FireWire, easier RAM access, slot-loading DVD drive, better speakers, sleeker chassis, etc.) was a really nice step up from the original tray-loading models).
iPad is the same. As popular and strong-selling as it is, imagine how it'll be when it actually sports the features and capabilities it should've from the start?
Look for 2012 (or maybe 2011, but I'm not sure...depends on how well they update it) to be when the thing truly hits the stratosphere. Until it gets FaceTime, which it should've had already, I think a lot of people are going to hold off. I know quite a few doing exactly this.