So I just started playing wow again after a 2 month break overall I've been playing since vanilla but had a large break between the end of BC and mid way through wrath. I was rather disappointed with both wrath and cata from a gameplay point of view, they tweaked the talents a little and such but overall the effort they put into the content in comparison to BC was average (raid/dungeon wise).
So anyway, I have yet to play the MOP beta though I do have a few friends who are playing it and I have been watching them stream, I think that MOP may actually be a slight comeback for the behemoth that is WoW. Yet again they are revamping the talents and in my opinion it is for the better, it is broadening the range of ways to play a class and spec by quite a lot, which I personally think is a fantastic idea it means there will be much more unique and you wont just be copying builds from the top players, sure there will be things that are better than others but the fact that you can mix and match different specs to a degree allowing for a much more personal touch to your spec is rather interesting, for example you could be playing an assassination rogue with shadowstep, just an idea.
Now I was a little skeptical about the introduction of the Pandarian race, I guess mainly because seeing random pandas running around just seems a little odd I guess, but I quickly got over this remembering that Pandarian is one of the original races in the lore and as mark said they should have been introduced earlier rather than space goats (though I prefer the term space cows) and after watching some beta streams they really don't seem too bad at all and I think its a move in the right direction, they really need to bring back the original content from the warcraft series.
A quick look at the monk, my knowledge isn't that great on the new class but from what vie seen and heard I think its an ok idea kind of a mix between a shaman and druid is how some people have described it. In my opinion im nor for or against it, I cant really say what side I'm on as I haven't tried them out nor do I know much about them but I think it is rather interesting and WoW really does need some more classes I think.
It would have been nice to see them release 2–3 classes in MOP though I think with with the new talents it will be much more interesting and hopefully will last till the next expansion though I don't know how much longer its going to be around for as there are a few new MMO's coming out that will give wow a run for its money (TERA & GW2), I hope it goes for another few years but they really have to stop bumming around and actually bring in some really interesting and fun content rather than just mindless grinds and such. Basically they just need to make it hard again. BC was good because it was a challenge and you had to work for things but now you can do raids in raidfinder and not even bother with the strategy its so basic, which is a shame because some of the raids this expansion had some potential but they just didn't quite make it.
Overall I think MOP has potential to bring WoW back, not to what it was at its peak but hopefully somewhere close to that. Lots of people aren't too happy with MOP, don't be over skeptical try give the beta a try, watch some streams don't just base your opinion on word of mouth, because thats what I originally did but then I really looked into it and was actually surprised. All I'm asking from them is don't screw this up. Its really that last chance they have and if MOP is a flop (couldn't help myself) I'm going to go play Guild Wars 2.