Your best bet might be to give people a rundown, give an idea of points values and what you/ they may be taking....
Generically anti-armour gear, whether magic or troops should be a priority, also, be prepared to face elite troops and tooled up characters. WoC can SOMETIMES (but by no means always) fall down in manouverability and numbers, though this is by no means a certainty...
I don't have much experience against the latest WoC but if you can give people a better idea of what you need to know precisely, they might be of more help than me.