From the ones you listed:
Dell 3007WFP-HC is an LG/Philips S-IPS panel. I think the best in your list by far.
Dell 2709W is a S-PVA panel. A good middle ground if you play games since it has a faster response time of 6ms.
Dell 2408WFP is also an S-PVA panel just a tad smaller.
The Mac 23" panel is also an LG/Philips S-IPS panel, but older than the model in the Dell screen. Visually it should be on par with the 30" dell. I highly doubt it is outperformed by the two PVA panels.
By the way the Mac 30" model is an identical panel to the Dell 3007WFP-HC.
For colour correct work a IPS panel is the way to go. Large viewing angles, which becomes even more important as screen sizes increase. PVA panels aren't bad, but they are a middle ground between IPS and cheap TN panels, the later which are excellent for games because of their near instant response times and insanely cheap price. Note that all the monitors in the list are wide gamut displays which means you will NEED colour managed applications that recognise the colour profile from your screens driver (or your calibrator if you have one) and convert the colours to look correct on your screen. That is unless you like pink people.
If price conscious the Dell Ultrasharp 2007FP may also be the way to go, either a Samsung or an LG/Philips IPS panel depending on which batch you end up with. This screen is not a wide gamut screen.