I still looked up the current status of the Gunner and they're still not very impressive. Normal shots don't stun and 10 STR or INT = only 2 max dmg. The strongest skill is only 500% multiplier with a 6 second cooldown and the current guns (those dual wield handguns/pistols) might only be as strong as a fully upgraded HLB at best, or a bit weaker... The other skills are more than 6 second cooldown except for Reload, which is about 3-4 seconds after r9...
We'll have to see how this class gets tweaked here and there during and after testing. Are there anymore videos that shed more light on gunners? My search on YouTube only had this video, someone playing the destiny tutorial, and a short skill demo.