Here is a summary of all the leaked details from EGM magazine. The scans which had been posted earlier on have been taking down. here is the full transcript from the magazine.
Flare - It's a flashbang. Seems Forerunner in design, definently the unknown grenade type.
Mauler - Dual-wieldable shotgun. Brute weapon, mandatory blade randomly sticking out the bottom.
Gravity Hammer - Based on Tartarus special toy. Can act like a sword, but mostly used for area attacks and physics based fun. Sends vehicles and grenades flying. Has a shockwave-type effect.
Regenerator - Equipment. Like the power drainer but opposite.
Radar Jammer - Equipment. Causes radar to go crazy with false positives. More importantly though, described as "mostly" useless in the campaign. Yea, okay I guess it's just a turn of phrase.
Positional Shield - Equipment. Pretty much exactly like the ground shields in Halo/Halo 2. Not clear whether or not it's permanent or whether or not it lets gunfire through one side.