Using CursorFX here too and LogonStudio Vista works also.

The only Stardock game I tried so far is Galciv 2 ToA. It complained about missing DirectX at startup but it ran just as well as it did on Vista.

• DesktopX: works mostly ok (apart from new ActiveX visibility issues, who would have thought? )
• BootSkin: not tried, probably doesn't work and IIRC the boot animation is in a signed dll, so SD will have to find a way to work around that, if at all possible
• CursorFX: working fine
• DeskScapes: apparently it's working for some people by using the Vista Dreamscene dlls, not tried
• Fences: working fine
• IconDeveloper: working fine
• IconPackager: don't install it, it will mess your icons...
• KeepSafe: seems to be working
• LogonStudio: updated with the new Windows 7 way to change the logon background
• MyColors: not working, as it's still using WB6
• ObjectBar: starts ok and seems to work. Not tried much further
• ObjectDock Plus: working fine (but I'm only using a tabbed dock and an auto-hiding dock with only shortcuts and no tasks, so I don't know if the start-menu/tray/task handling is working ok or not)
• Rightclick: crashing Explorer sometimes when right-clicking the desktop. Not sure if it's a problem with Windows7 or Fences (I remember seing a report of that somewhere). Only shows on second click (ie. it shows the standard menu and then the rightclick menu)
• SkinStudio 6 : not tested
• SoundPackager: not tested
• Virtual Desktops: not tested, but the taskbar applet is not working in x64 anyway. Should still work through OD/plugins
• TweakVista: not tested
• WindowBlinds 6: not working
• WindowBlinds 7: in private alpha, no idea when it will be available to us
• WindowFX: not tested

YMMV and since none of those are supported, you're kind of on your own if it breaks, but that should give you an idea of what is working.

Bootskin is OS-specific. Trying it on one other than it is made for will only break windows, as some people who ignored the warning found out the hard way.