I picked up a couple of 3rd-party batteries, making sure that reviews indicated that they were compatible with the new electronics in the 7D that "track" batteries -- ie, battery #1 has been used "x" times, and so on.
The good news is that I was able to register one of the 3rd-party batteries with the camera, so it recognized it separately from the Canon battery that came with the camera. The bad news is that the other 3rd-party battery seems to be indistinguishable from the first one -- it literally thinks both of the new batteries are the same. My guess is that they've got one chip for all their batteries answering the same identifying number to the camera. Not the end of the world, and both batteries seem to work ok, but they're not *quite* the same as genuine. FWIW, I haven't done any real measurements to support this, but I think the battery life of the replacements is marginally less than the genuine article. Again, not the end of the world, as I'm really pleased with the amount of shooting I can do on a single battery as it is.