Multi monitor setup?

[Sega Mega Dave]

After looking at the tft picture thread im wanting to look into a multi monitor setup. Either 2 or 3 and i want them to look like one monitor.

I am running an overclocked GTX580 and an i7 2600k at 4.5ghz.

My pc is pretty much a gaming rig if thats important?

Basically with the above setup would it be best go for a dual setup or triple?

Also apart from monitors what else is needed?

Will fps be effected a lot with new resolution, will games still max out?

Or do you think something like one 2560x1440 27" monitor? If not which monitors would you go for the multi setup?

Thanks Dave