If your going out just to have fun, take your friends. If your going out to meet someone, go alone. Most ladies hate it if you bring your buddies with you when she asks you up for a night cap....plus, that's kind of gay, isn't it?
Truthfully, if you are an extrovert, it makes no difference if you arrive somewhere alone, you'll likely not leave that way anyway. Live on the edge. Give it a try.