I am pretty green in terms of PVP, so ill share some thing I discovered that work pretty well in the arena matches and continue to add on as I play more. NOTE: All of my "discoveries" and tactics are based on heavy feral druid build (ie pure DPS and killing mode vs healing, mass CC, etc)
Cyclone / Heal Combo
I didnt ahve success cycloneing people when it was still 2v2 or 3v3, but if you manage to tip the scales in your favor by killing another player, OR its 1v1 with your partner and their partner dead, this is a great tactic for healing up.
Pop out, cyclone other guy, and use that 6 seconds to cast healing touch then instant cast rejuvi, or use 6 seconds to cast regrowth, rejuvi, lifebloom. I used this a LOT and it almost never fails...one time I delayed too long in casting and a shaman earthshocked me mid cast, but other than that it has worked out well.
Go to bear form vs warriors
If you have to take down a warrior solo, bear form works better IMO for a couple of reasons. One, that warrior may be arms / fury and have the talent that hits you for mega damage IF you dodge an attack....my cat form ddge % is in the mid to high 30's, so this talent means me fighting him equals almost instant death since I will dodge like mad. You still have high dodge in bear form, but the extra armor can help mitigate his attack.
Mages are your friends
Your high DPS + soft soft cloth target with low HP = fun :) If you see an open mage thats distracted, or you start out stealthed, get that mage if you can. I have almost 100% of the time had a mage down to 20% or less when they even realize you are killing them and cube / blink away...just chase that mage down (shift out shift back to get out of cube)...it only takes another 1-2 mangles to seal the deal. Or, make sure you get in your bleeding effect finishing move...with a mangle intesnifying all bleeding effects, he may blink away only to die from your bleeding effects.
Stealth on Stealth
IF you have the three points in improved stealth, you have damn good stealth considering your a NE (which improves your stealth) plus the talents...you also have really good stealth detection...if you are doing 2v2 think about having the other guy be bait for the other teams stealth unit...you have a decent chance of seeing the rogue before he wraps around and stuns your teammate, and you can pounce him and both can wail on him.
1: Mages who blink instantly might mean your well past dead ;)
2: Cyclone almost never worked for me, so dont expect it to last as long as 6 seconds...if theres a way to get out of LoS of anything then do that while casting heal
3: You cant hit crazy hard in bear. Even in bear form you probly will die against any arms/fury warrior...imo...mine as well get a bit o' damage on the warrior in cat form then suspend the fight
dunno man...experiences may vary I guess :) I tend to be a big mage killer...the way our team is setup too usually uso or lyte is the primary target, so I can kill without being bothered....cyclone never fails for me, and I have zero points in balance...so meh...
druids are fun
to kill...
the only losses gren and i really have from them are ones where they are cat form and get lucky crits on gren. If they go after me it's over since I can absorb too much dmg for my own good...
10k hps + 20% dmg goes to my pet + VW shield (fel dom..usually i run with guard out...) = around 15000 hps = <3 :D
tactic for casters:hit, run to nearby pillars, OWNED 8)