Congrats to the VirtualBox team on being the first (that I know of) to provide a working Seamless/Unity/Coherence mode for OpenSolaris 2008.05 guests on OS X. (I don’t know how long this has actually worked, I only tried it last night, in VB 1.6…)
Obviously a bit of work to do before it rivals the sort of integration that Windows guests enjoy in Fusion and Parallels, but it’s a good step in the right direction…