There are two main complaints: first, that Blizzard doesn't supply any onsite Arena servers. We know this is true -- Blizzard has event servers that they use for events like this, kept offsite so they don't have to set them up all the time. But GotGame claims that this causes problems -- as much as 300+ ping, which in the quick world of Arena matches, is practically unplayable. We're not sure why Blizzard doesn't allow setups on site, but that seems like a reasonable step to take if they're serious about making professional Arena big.
The second is a little tougher: this post claims that Blizzard has brought the pro Arena servers up to the Season 4 patch, but locked the gear down at Season 2. Our own Zach Yonzon says he's not sure where the Arenas are -- he doesn't believe that official Arena matches are underway after Wrath yet, and if that's true, then Blizzard may already be updating this (bringing the gear on the realms up to level 80 levels to match the talents). But either way, it's strange to hear someone say that Blizzard isn't supporting professional Arena matches correctly. You'd think that if they were as into supporting WoW as an e-sport as they say, that they'd address some of these concerns.