The Haunt pets last 60 seconds, but are pretty fragile and can be killed. With enough recharge, though, they can be made perma.
http://tomax.cohtitan.com/data/power..._Control.Haunt
http://tomax.cohtitan.com/data/power...?id=Pets_Shade
Phantom Army, on the other hand, ALSO lasts 60 seconds, but can NOT be killed, which is why it may seem to last longer.
http://tomax.cohtitan.com/data/power..._Control.Decoy
Umbra Beast, of course, is the same as the level 32 Control set pets such as Jack Frost, Animated Stone, and Fly Trap - its duration is so long that it might as well be permanent (IIRC it's a 23 hour duration or something like that), but it can be killed.
Also, note that there is a bug right now with Umbra Beast (which will be fixed next patch or two, the devs say) where it is in 'defensive' AI mode and will not attack unless it or its owner is being attacked. This makes it less useful when all your enemies are held/stunned/whatever, but the patch will make it just as 'aggressive' as all other controller pets soon.
My darkness/dark Dominator is at level 18 atm. I was expecting the Haunt pets to remain with me (Phantom Army last longer than them in my opinion) Once I hit level 32, will the Umbra Beast stay with me like the other controller pets or will it disappear into the sunset? lol Help please thank you