Yesterday I tried the beta of Ubuntu 11.04 on VirtualBox.
I can say it works well, but on my laptop (core 2 duo 2.16) it is slow.
I used Oracle VirtualBox 4.0.4r70112 with VirtualBox extensions.
In the following few lines I show you my VirtualBox configuration:
- 971 MB of RAM
- Single processor without PAE/NX
- 32MB of RAM video
- 3D/2D Acceleration enabled (without these the unity doesn't work)
- Windows Direct Sound ICH/AC97
- NATted network
- Controller USB2.0 on
Then I've installed the VirtualBox Guest Additions.
All is working fine.
To install the VirtualBox Guest Additions you shall update your system and then install kernel sources and kernel headers. Last you can run the VirtualBox Guest Additions installer.