Check this site, http://www.flatpanels.dk/panels.php

Not sure how often the DB is updated, but according to it:

Dell 2007WFP (*) (widescreen) has a 20 inch 16 ms S-IPS (LG.Philips LM201W01 eller LM201WE2) panel.

I just recieved my 2007wfp on Friday and it has an S-IPS panel. Thus far, I don't think there's ever been a switcharoo on this model. It's an LG.Philips LM201W01. Some have said the other type was just a rumor, or only existed in limited amounts early on, at any rate.

DakkonA: Which revision did you receive?

A02. But when they were swapping panels back and forth in the 2007FP, they don't bother with a new revision number, so that wouldn't be helpful if they were doing that. However, I so far haven't heard of any instances of 2007WFP with any other panel type.

Only the 4:3 monitors came with S-PVA or S-IPS panel.

The 16:10 (wide screen) monitor - 2007WFP - is S-IPS only. It's the same panel used by 2005FPW in fact.

the site also claims 6ms for the 24" while Dell says 16ms:

"Dell 2407WFP (*) (widescreen) has a 24 inch 6 ms (g2g) S-PVA (Samsung LTM240M2 eller LTM240L2) panel."

The 6ms rating is gray-to-gray, and the 16ms rating is black-to-white-to-black.