VMWare Fusion 3 comes with a tool called VMDKMounter.app. It allowed you to simply double-click NTFS or FAT32 VMDKs and they would be mounted on your desktop.
VMWare Fusion 4 dropped this tool, but you can download version 3.1.3 and extract /Library/Application Support/VMware Fusion/VMDKMounter.app from the package using Pacifist (just make sure that VMDKMounter.app/Contents/MacOS/vmware-vmdkMounterTool has the sticky bit set and is owned by root:wheel after you extract it).
VMDKMounter attempts to mount EXT2 using /System/Library/Filesystems/ext2.fs/Contents/Resources/mount_ext2, so we need to create two symlinks:
sudo ln -s fuse-ext2.fs ext2.fs
sudo ln -s ../../mount_fuse-ext2 mount_ext2
Now we’re all set, you can simply open a VMDK by double-clicking it, or you can right-click a VMWare VM and open it with VMDKMounter.app and automatically have all its VMDKs mounted.
If you are receiving an NTFS-3G error message when mounting a non-NTFS VMDK: that’s perfectly normal, so you can just click OK. The error message is due to VMDKMounter simply trying a bunch of file system mounters until it finds one that doesn’t fail. As far as I can tell, it tries (in that order) ntfs, msdos, ntfs-3g, hfs, ext2, ext3.