Can any forum expert enlighten me on the above? I have the X220 tablet IPS screen and it is very clear with good colour reporduction and clarity. Does it compete in anywway with Apple's new Retina in terms of quality?

Thanks in advance!

The X220 IPS screen is very likely 6-bit (262k colors only) e-IPS panel. The Apple screen technology is unknown but I guess it is the same.
There are color spaces:
http://www.notebookcheck.net/Review-App ... 959.0.html
http://www.notebookcheck.net/Review-Len ... 639.0.html

As for color reproduction, I bet that none of them can compete 10-bit NEC / Eizo professional desktop monitors with (W-CCFL) backlight uniformity compensation. Still, both of them are superior displays comparing to ugly TN crap in most of current notebooks production.

Thanks Puppy, that is very informative. I guess I have no reason to jump ship to Apple and sell my lovely X220 IPS tablet!

The Retina display has got to be much, much clearer than the X220 tablet IPS. First, the Retina screen uses many more pixels to construct every bit of detail, and second, the tablet has an extra touch-sensitive layer that distorts the screen somewhat. Puppy's links show that the Retina screen is slightly brighter and higher-contrast as well.

One thing I have been saying is, get a tablet PC only if you require the touchscreen technology. If you just want IPS, there are other far better choices (Apple's Retina, HP's and Dell's 15.6" business laptops, and several ultrabooks). The fact that you are considering getting a Retina Macbook Pro implies you don't really need a touchscreen.

I have the Retina MBP and used to have the X220 IPS. There is no comparison, the resolution on the X220 is too low to come close to the level of detail and smoothness you get on the rMBP. Text is simply stunning and you could almost dive into photos. It is the best laptop display I've ever seen.