Somebody has asked me for advice about buying a monitor, expecting me to know what to tell him. Help! ;(

He's looking for a jack of all trades monitor, budget up to £300 (more like £200), which performs well in 3D applications but is also good for casual gaming (MMO, Diablo 3 etc). Preferably around 27".

I know there are a lot of talented folks on this website who are interested in 3D stuff, hardcore gaming and also keep up to date with hardware so I figured it was worth a shot asking! I really have no clue about modern monitors as I've deliberately used a CRT for the last 14 years or so and not bothered to keep up to date (I know, I know)...

How important is refreshrate etc? Any specific brands or models?

Any advice would be appreciated. :)