Well, like the topic says.. when do you use it? because when in catform you don't have any stun attacks except pounce? However ain't it better to use ravage that does more damage then both shred and pounce together?

Now to my second question, on the bases i wrote above.. it seems that it ain't worth putting points on improved shred? Am i right or wrong? Would really like some help with these questions.

As an opener, yes ravage is almost always better. If I come up to a healer many times I will use pounce to interupt his healing. But other then that ravage is almost always the way to go.
As I am 60 and mainly only pvp now improved send is really really nice. You can get 2 shreds on a full bar. However when I was leveling it didn't make sense for me to do this since you are only behind the target once then face to face the rest of the time unless of course your grouped(which I found fastest way for me to exp most of my lvl was solo with lots of mobs)

Yeah, think of using it more as the Main Assist in a group than when solo. The mob should be facing the tank so you can sit right behind him and shred away. For many cats its their primary means of dps.

If I can get behind the person, I will always choose to shred over claw. Burst DPS is what wins in PvP and Id rather hit a 900 shred than a 400 claw any day.

i would go with improved shred over regular claw dmg myself. claw is great to build fast combo points, but improved shred hits harder, and doesn't require that much more energy.

i think there is a guy who analyzed druid dps and created a calculator and simulator. shred (improved) out dps'd regular claw attacks based on the calculations. the guy even calculated the exact amount of atkpwr we need before agi > str to maximize our dps output. hmm, forgot where i found it. anyone know what i'm talking about?

Again, the key here is getting behind the person. If someone else has aggro and you can stealth up and ravage and still not pull aggro, you will be far better off using shred. More damage per energy.

Though solo'ing its almost never used, as it's impossible to get behind a mob, considering we don't have a combat stunlock like rogues.

For pure Dps in groups though, Love Improved Shred.

PvP non-stealthed and usually engaged targets and in instances in which I can get behind the mob.