The MM17D is a 17" 8ms model, the MM17T is the same as the 17D but with multimedia speakers. The PM17T beefs the speakers up to 2.5watts. Finally the PM17TU is a 3ms 17" part.More info over here.
The most interesting thing to note about ASUS entering the UK LCD market is not the actual monitors, rather the warranty. For the first year of the monitor's life there is a Zero Bright Dot (ZBD) policy. That's the longest policy of its kind thus far, which is fantastic news for the consumer: "It’s a strong statement, especially when you consider all of our competitors are offering only 1-3months ZBD policy", says Hiten Desai, product manager of LCDs for ASUS UK.
ASUS to launch LCD displays with dead pixel warranty

Hexus reports Asus will soon launch LCD displays to the UK market. The company has lined up three models and a fourth one should follow shortly.