During beta there were alot of complaints about the fluidity of abilities, the fact that they didn't happen at the exact time you pressed the key but were delayed by server lag. Towards the end of beta they addressed this in a patch by making the animation play immediately but the actual serverside checks still took place and the ability would still "fire" at the same time. You can see this when you try to attack on enemy who is not flagged for rvr, the spell or ability starts to fire but once the server tells the client its a non attackable target it stops and you are given a message to that effect.
While this has improved the feel of the action somewhat, it seems that theres alot of cases especially with melee where the latency causes problems such as out of range or positional errors.
It has been suggested to them previously that checks for range and position should also be moved client side and only the actual timings and damage calcs should be on the server, meaning if you swing at someone and they are in range, even if they move out of range during the time it takes for the server to register your move, the server has been told they were in range at the start of the action and therefore its a succesful attempt. Wether or not they take this onboard and patch it in is another story, but so far they have been good at listening to feedback. In fact if the report bug/feedback is still ingame I'd suggest sending them a quick report. Theres cases where I'd found strange bugged textures in remote places and they fixed them within a patch or two (although my floating tree bug report that mentioned about 20 trees floating jsut above ground never got addresed :p )
Overall I'd say don't give up the tanks feel alot better around 20+ even with the weird anomalies, and if you feel frustrated just pop on another char and nuke people for revenge! Wait till you get "gork sez stop" on your shammy at level 8 or 9ish and just lol at the noobs dropping like flies
