Winterboard is still messed up. It seems to only apply certain themes and tweaks. I got Glass Orb Color installed but nothing I've downloaded since has worked.
This is mostly due to every graphic file being duplicated and renamed for the iPhone4's higher res display. For example for the icons, there is now icon.png and icon@2x.png. this applies to almost, if not all, pngs. until the themes are updated, you'll have issues.
Happens when you SSH icons as well. I imagine its the fact that I made my icons 114x114 but failed to use the 2x file name, so its pixel doubling them.
I bought an iPhone 4 yesterday, jailbroke and installed Winterboard on iOS 4.0.1. Working fine with one SB theme (Aqwoah), an SBSettings theme, Backgrounder badge theme, and one LockInfo theme (High Gloss). So far everything is working great.