If you don't care about WoD game mechanics? Don't read more.
Checking the vampire line, 3rd Edition pg.208 says that every Succ after the first on the 'How much did your skill help out?' roll adds an extra die to 'How damaging is the weapon?'. Doesn't say if it only works for one type of attack or another though, so the implication is that it's across the board?
Vampire 2nd Edition pg.224 has it that firearm attacks get to add the 'How much did your skill help?' successes (without the -1), but Brawl and Melee attacks don't get to add anything.
Vampire 1st Edition pg.149, the 'How much did your skill help?' firearm successes are added to the damage and not the dice rolled to check damage, while Brawl and Melee just get additional dice (pg.148).
So if you get 3 succ in a 'How much did your skill help out?' roll for a 4-die axe or a 4-die pistol and now want to check damage?
3rd Edition - Roll 6 dice for the axe. 6 dice for the pistol.
2nd Edition - Roll 4 dice for the axe. 7 dice for the pistol.
1st Edition - Roll 7 dice for the axe. 4 dice + 3 Damage for the pistol.
..and folks wonder why arguments break out mid-combat on MU* that have scant news files. Oh, and I could use some feedback on this ( http://www.livejournal.com/community/roleplayers/870052.html ) -- myself, I'm preferring Thought the First.