Unless the camera firmware allows zooming in to 100% of any selected portion of the image, no. 460,000 LCD pixels is not enough resolution to judge focus for a low-end digicam, let alone a camera with >20,000,000 pixels. If you need to check focus critically, shoot tethered.
Unfortunately, I can't shoot tethered until a more portable solution comes along.
This new screen for the H4D 60 is twice the resolution of the one on the Canon 1ds III, which I heard is pretty good, though I've never seen it.
I would guess, though, if this new screen were all that great, Hasselblad would be touting it more.
Anyone from Hasselblad on this forum that can report a hands-on look at this screen?
And is it planned to go on all the H4D models in the future?