Parallels Desktop 3.0 conflicts with MacFUSE 0.4 and NTFS-3G
MacFUSE 0.4 and NTFS-3G won't work properly.
Parallels Desktop SmartSelect won't open Windows files in Mac OS applications.
The problem should be solved in Parallels Desktop minor update coming in the nearest future.
Before the update the only solution is uninstalling the applications that cause conflicts and reinstalling Parallels Desktop 3.0.