A minor patch is being deployed on the live servers taking the current build to 3.0.8a.
It appears that three minor changes are part of the patch.
"Howling Blast has a 5 sec cooldown. There is a tooltip error where it appears that the spell has no cooldown, but the game will still enforce one. Sorry for the inconvenience. We plan on getting the tooltip corrected as soon as we can." - Ghostcrawler, Blizzard
"There is a known issue in 3.0.8 where some Aspects behave as if they still have a global cooldown. The design is that Hunter Aspects should not be on the GCD. We are investigating and will try to get this fixed as soon as we can." - Ghostcrawler, Blizzard
"We had to make a change to the new warlock summoning mechanic at the last second to prevent an exploit. Our apologies to all the law-abiding warlocks who have to suffer with a painful cooldown on your summon in order to fix this problem.
We plan on getting the Ritual working correctly as soon as possible. You won't have to put up with a 2 minute cooldown for more than a few days. Standard caveats apply that this could change for any number of reasons, but we wanted to keep you informed of our plans at this time."
Official patch notes will be posted when they become available.