Someone dating regularly
For the greater good of humanity, I decided to ask one simple question: When you say you're "dating" someone, what does that mean to you?
But if I'm dating someone in the present tense, that's probably someone who I'm hooking up with exclusively and seeing regularly, but we don't have the label yet.
I wouldn't refer to a current boyfriend as 'the guy I'm dating.' Past tense is used more loosely.
As far as I'm concerned, there are two types of pseudo-relationships you can be in that aren't real, bonafide relationships: You're either "hooking up" (casual booty calls, probably not going anywhere) or you're "dating" (going on dates, getting to know each other, hopefully going somewhere).
I would say my boyfriend and I were "dating" long before we were in a relationship.
While hooking up involves a bunch of late-night booty calls that don't necessarily need to lead up to anything, dating is time spent getting to know someone, trying to figure out whether or not you're going to take the next step and pursue a real relationship.