I came across some interesting tips on things to consider in a virtualized environment by Greg Shields (Consultant and Microsoft MVP).
They are non-issues (or settled issues) on physical environments and you might overlook them when making the transition to virtual machines.
Here's a summary to get you interested:
- Managing from the console
- AV on VM disk files
- Power options
- Cluster Failback
- RAM availability
- Backup for CSV
- Number of processors
Here are the links to the actual articles: