I can't believe you've been waiting this long to watch HD content. If your second HDTV isn't at least a 32" screen, and you're more than 3' away from it, there's no point in waiting for a dual-HDMI box; your eyes won't be able to tell that it isn't HD. And to the people who want to argue about visual acuity, the OP has been watching SD content for all of this time already.
Pick up a 722k with the awesome 21.0 remote, and be happy for a long time. Regardless of whether you use TV2 as an SD discrete output or just run a mirror as sandman said, the 722k is a good box, and the 922 won't solve your problem (unless your second HDTV is a Sling client).