There are two yoga mats that are top of the line. Manduka and Jade Mats are the most sought out ones. The difference between the two comes down to how they are made. Manduka is made with a closed cell structure. This means that if you sweat all over it, the sweat wipes off and does not soak into your mat. This is a great selling point, as you are not carrying around a mat that smells like all of your yoga practices. Manduka's can also be easily hosed off in the shower to be cleaned. Just throw it over the shower, use a body puff with a little bit of dish soap and give it a good scrubbing. Rinse it off when you are done. Jade on the other hand has an open cell. It is like a sponge. It will soak up any sweat or liquids. What I have seen is that Manduka's can honestly last you a lifetime. I have had mine for 6 years, with a daily practice, and it still looks almost brand new. Jade mat's however will need to be replaced every few years.
As for different versions of the Manduka mats, I prefer my Pro-Lite mat over the Pro Black series. The Pro-Lite is lighter and easier to take with me to classes, but thick enough for padding under my knees. The Pro-Lite weighs 4lbs compared to the Pro weighing 7lbs.