VMWare ESX server has a bunch of command line utilties to display and modify the ESX server configuration, and the vast majority of them are buried in the /usr/sbin directory. One useful utility is esxcfg-nics, which displays the NIC type, the virtual NIC name, and the current configuration of each NIC in a server:
$ esxcfg-nics -l
Name PCI Driver Link Speed Duplex Description
vmnic0 02:02.00 tg3 Up 100Mbps Full Broadcom Corporation NetXtreme BCM5704 Gigabit Ethernet
vmnic1 02:02.01 tg3 Up 1000Mbps Full Broadcom Corporation NetXtreme BCM5704 Gigabit Ethernet
If you haven’t had a chance to play with ESX server 3.X, I highly recommend pinging your VMWare sales team to get an eval.