Maintenance includes hardware upgrades and bug fixes but most noticeably they are implementing the phasing technique they use in the first zone Tanaan jungle on the garrison and other zones.
Don't know about you guys but Tanaan was flawless for me, Infact most of WoD is with the exception of Garrison and the close proximity areas.
So far I'm loving it, seeing all the old Orc names from previous expansions is a nice touch, getting all the little bits of treasure and killing the silver mobs is fun and a nice exp boost
And when I have been able to use my garrison it's been fun, I actually have 3 followers now of which 2 are epic quality. And I have both my profession buildings from quest lines, although only tailoring built
The quality of this expansion is brilliant it's just the execution so far that let it down, but I will give a loss their dues, rather than their normal silence it seems we are getting almost hourly updates on the state of play which imho is good to see, atleast it shows they are trying