Looks like it works. I checked with Symantec, they say they don't support Beta OSes but if you were going to try to do it, this is how you should, not that they're saying nuthin'...
You have to use version 11.0.4. Run (as admin) LUSETUP.EXE to install liveupdate, reboot, and then run SETUP.EXE.
Works for me. (W7 build 7000)
Hello,
I joined SevenForums.com specifically to say "Thank you!" for posting this. I Googled and found your post. Being able to use SEP was important for me b/c I get it free from work and frankly, I think it's the best AV program out there...I have no issues w/it and it works great for me.
I'm running
Build 7100 (64-bit) and it's working perfectly; with a couple of side notes:
1. There is no Network Threat Protection; that is no longer on the screen. However; AntiVirus/Antispyware and Proactive Threat Protection are there and have the latest (today's!) updates

.
2. The right-click a file/icon-->"Scan For Viruses" option seems to be gone. That's unfortunate; maybe there's an option in W7 somewhere to "define right-click behavior?"
How I Did It
I installed Live Update (LUSETUP.EXE) and rebooted. I then did an Unmanaged Client install. Only thing to note is that when you go to update the virus defs/AV software it takes a really long time.
First update it downloaded about 50MB worth of updates; went thru the usual "Downloading AV Software", "Downloading AV Defs", "Downloading Proactive Protection Defs" etc. Then it just sat there for a good 30 minutes at least.
Have patience! It is not frozen! Even though CPU activity was almost nil, it was "thinking" during that time. Eventually, you'll get a "You must reboot" popup.
Upon reboot I got the "Your AV defs are out of date" popup. AV was current but Proactive wasn't. I run LU update again and it went through the same 30-40 minute-long update...and then it was good.

It didn't ask for it but I rebooted anyway....always a good idea when updating an program.
I really hope that SEP works with the final build! I hope to make the upgrade to W7_64 when it comes out. I skipped Vista and am ready to move forward from XP. See you all around the forums.