Unless there is some strange functionality you need from VMWare that isn't supported in VirtualBox, I suggest giving it a try.
FTFY
You do have to re-enable the source manually - it's not deleted, but the 9.04 -> 9.10 upgrade process turns off third party sources as a precaution.
Just finished upgrading an AMD quad core box, smooth sailing.
http://patrickmylund.com/blog/how-to-install-vmware-tools-on...
As opposed to running Ubuntu under VMWare
I am still hoping for a reliable/official VMWare Tools .deb repository.
I am having one of those days. I read 'VMWare Tools' as 'VMWare Server' for some reason. Cheers!