Infoworld reviews VirtualBox 3.1
There is an interesting review about VirtualBox 3.1 at Infoworld: InfoWorld review: Desktop virtualization for Windows and Linux heats up. Let’s forget for a moment that they don’t mention the advantages, when you use it with OpenSolaris (DeDup on VMs anyone?). But the review is really positive anyways:
It all began when Sun Microsystems acquired the product from little-known German developer Innotek. With Sun's engineering resources behind it, VirtualBox quickly grew from its role as "the little VM solution that could" to today's technology leader in desktop virtualization scalability and manageability.
[...] and that Sun's decision to gobble up this diamond in the rough is looking less like a compatibility play for OpenSolaris and more like a clever way to acquire a potentially class-leading VMM (Virtual Machine Monitor) with which to pry loose VMware's stranglehold.
But read for your own.