I know support for 7 would be nice, but then again, why do you think a fresh device of today magically just works with all it's new features on an application developed two years ago?
It would be nice, yes. Still it would be very unlikely, too.
There are plenty of new MIDI controllers released every month that work with old software.
And I'd expect it to work because the product page on Ableton's website states that you need Live 7 or higher. These are the published specs on Ableton's website: http://www.ableton.com/launchpad
"Software system requirementsLaunchpad
requires Ableton Live 7 or higher.
Mac: Any G4 or faster (Intel Mac recommended), 512 MB RAM (1 GB recommended), Mac OS X 10.3.9 (10.4 or later recommended), QuickTime 6.5 or higher, DVD-ROM drive
Windows: 1.5 GHz CPU or faster, 512 MB RAM (1 GB recommended), Windows XP or Windows Vista, Windows compatible sound card (ASIO driver support recommended), QuickTime 6.5 or higher, DVD-ROM drive"
It doesn't suggest that any of the advertised functions wont be available with a version before Live 8. If it says you need L7 or higher, why would I assume it wont work properly with Live 7? They mention minimum and recommended specs for RAM, why not a min/rec version of Live?