But unless Apple plans on offering 1080p content on iTunes, that feature would be of limited use to the majority of consumers.
Why say this? Why continue to feed the perception of it as a one-dimensional product (only content from the iTunes store is applicable)? For the majority of consumers the first source of content for iTunes was NOT the iTunes store but ripping their own CD collection.
With

TV, content is sourced from many places other than the iTunes store. For example, an iPhoto collection probably has NO photos "purchased" from the iTunes store, yet they flow to the home TV via

TV.
Ripping a DVD collection is far from the simplicity of ripping a CD collection, but it can be done... and is done... to make the personal movie collection readily available on the home TV via

TV (no iTunes store link required).
Almost every decent camera and any camcorder can shoot video. Apple provides tools (like iMovie) to edit that video. Renders from iMovie can go right into iTunes. Those will easily play on

TV too. Personally, I have our whole home (family) movie collection in iTunes and readily available on

TV (none of that came from the iTunes store).
Now, good cameras, iPhones and most HD camcorders shoot 1080p video. iMovie will edit & render that in 1080 too. It will go right into iTunes as 1080 content too. It just can't get from iTunes to the HDTV as a 1080p stream (the current model down converts it 720p). It is the ONE weak link in this Apple chain.
The point is that there are abundant (and legal) sources of content for

TV besides the iTunes store. It is not just a device through which to buy or rent content from there (even Apple agrees by adding other sources like Netflix support, airplay, etc).
I think it makes great sense to launch an 1080p capable

TV BEFORE there is 1080p content in the iTunes store. The hardware must lead. Until there is lots of 1080p

TVs in homes, there is no way for any studio to even test the profit potential of 1080p content for

TVs in the iTunes store.
Get the hardware going into homes and the software can follow. Between the time those 1080p

TVs start going into homes and when some Studio decides to test 1080p content, the

TV3 will still play all existing content to it's fullest potential, much like quad core hardware in Macs can still run software coded for single core hardware. Lead with the hardware and the software owners will be tempted to exploit that newer hardware (it doesn't work the other way).
Personally, I'm very encouraged by this new discovery. Hopefully, it's not another 4-year delay for the next round of new hardware. I've got 4+ years of 1080HD video shot on camcorders begging for a native Apple solution that doesn't involve downconversion to 720p. And for my own situation, I could care less if there is ever 1080p content for rent or sale in the iTunes store.