Wired mice can be up to around 5500DPI if you get a good one, and most wireless mice claim to be alot better than they are, but wireless mice are rarely advertised with a DPI rating.
Think about it, A Wire is much less susceptible to interference, the transfer speed will be higher, more signal can be sent faster. This would explain why ever 'Gaming' peripheral that is even half decent is always Wired
Look around for Razer and Saitek Cyborg, best imo.
definitely wired.
I get by fine using my wireless battery, though.
If you end up using a wireless battery, you should definitely invest in high capacity batteries. (whether rechargeable or not).