Originally Posted by
Frontenac
If I remember right the 5% increase is for base mana (without the gear). According to classicWoW.live, a Gnome Warlock will get 119 base Int at lvl 60, compared to 110 for a Human. That means 90 more mana, and barely more crit chance. When you add the gear, the difference becomes trivial. In Vanilla, racials were rarely game changers. Some are really useful (Shadowmeld, Will of the Forsaken, Warstomp, to name a few), but those stat and tradeskill increases were not that extraordinary to influence much which race you should choose.
Therefore, if you like your characters to be cartoonish, funny and the object of punting jokes, go Gnome. If not, go Human. At least rep grinds will be a little easier...