He's probably gonna need another 4GB stick of RAM too.
I know there's no time machine, but with that Staples deal last week and the prices on i7s dropping, coupled with Haswell coming this summer. I'd say $500 and under is the new sweet spot for 3rd gen i7s with no dGPUs. Also considering all the upgrades you'd still have to do with this machine after purchase.
6GB RAM and above should be the new standard. Especially for intro video editing.
Why would you do video editing in anything but GPGPU? Are you using Sony Vegas or something else horribly antiquated?