Yes, the new energy regen is great, and will allow a bit more micro control over your skills...
But when dps`ing in a pure dps setting, so long as a rogue allows the buffer zone for new incoming energy ticks/combat potency procs, and keeps up a flawless rotation.. the new energy regen will do absolutely nothing.
The most I could think the new energy regen system would do, is allow very few extra skills to be pulled off over the course of a boss fight. Especially if skills are dodged which would throw off the consistency of your current energy regen...
Anyways... to the people who scream OMG HUGE BUFF. I just don`t see it...
Over the course of 5 minutes.
Current system: Rogue will generate 3000 energy. (3020 when able to preload)
WoTLK system: Rogue will generate 3000 energy. (3001 assuming the first tick is instant)
The number of skills available will not be altered one bit, aside from the rare skill dodge which would throw off your rotation by a single tick.
It looks like the only reason for the new energy system pve wise, is for rogues who can`t manage their energy levels to take advantage of 100% of their ticks/potency procs, and rogues who skillspam and run out of energy reserves for kicks.
PvP on the otherhand, this will be awesome.
Although it is a nerf to our opener.. (not able to preload up to 130/140 energy anymore) it will be much more fluid once the fight has begun, so long as the rogue can keep spending energy and not lose his/her target, thus losing out on the 20 energy tick preload again.
I am way more excited with Kick/Arcane Torrent being removed from the GCD than the new energy regen system tbh....