Directory Opus (version 9.1.2.0.3429.x64 - which is the newest as far as I know) seems to work perfectly in Windows 7 RC1. When you start the install a warning pops up that says something like "this OS isn't supported".-Hirudin
You'll be fine with DOpus as long as you don't do something crazy like trying to replace Explorer. That's the only reason why that message pops up. Fortunately, you are smart enough to realize that so I'm just reiterating that for someone who is thinking, "Everything else seems to be working...let's give it a try." It won't work & windows 7 will not be amused.
Maybe that means slipstreaming is back too. 
Slipstreaming is gone never to return. It's all about WIMs nowadays. That's a shame because I thought slipstreaming Office & Windows was such a cool feature. Now the new way just seems like a hack.
Innuendo: if you don't need the "sneaky-stuff" that Daemon-Tools do, try out Virtual CloneDrive - free and works with win7.-f0dder
Virtual CloneDrive is inferior to MagicDisc. It's also free & works with Windows 7, but supports up to 15 drives and has image support for a lot more formats than Virtual CloneDrive including MDF/MDS and BWI/BWT. It's the only virtual disc program I've found besides Daemon Tools and Alcohol 52%/120% that supports MDF/MDS. No copy-protection & DRM support, though. One still needs Daemon Tools for that, but handles unprotected disc images beautifully.
And regarding vLite, yeah...using that is bad. MS even put up a KnowledgeBase article on that subject that basically says in a round-about way, "Hey, use vLite if you want to, but you're most likely going to have to reinstall Windows 7 if you do."
EDIT: Forgot to include the link to MagicDisc:
http://www.magiciso....gicdisc-overview.htm