Sounds like everyone's giving you pretty good advice, I'm just going to add my experience and tell you that there's as good of a chance that it will happen as there is that it won't....
At this time last year, my boy and I met each other at a party. We hooked up, I gave him my # thinking I'd never see him again. Well he actually called me the next day and we went out that night. I called him the following week and we went on a date the next weekend.....blah blah blah basically for the longest time we were together without the title....to be honest it sucked b/c we were hooking up and its not like either one of us could have dated anyone else without it being a big deal, you know? I was leaving for spring break and told him I felt like he was keeping me on the back burner until somehting better came along, and he explained that he loved dating me but wasn't ready for a relationship. I'm like, hello!!!! We ARE in a relationship! Anyway, I went to Cancun for spring break, had an awesome time, and then a week after I got back he asked me to be his girlfriend.
My point is, we did everything wrong (met each other while drunk, hooked up the first night, dated for 3 months without titles) but everything worked out. We're still together and totally in love. I can say that if it were to happen again I might be a little more "call me your f'ing girlfriend or were through

a little earlier on, but I saw in him that he was just afraid of being close to someone.
Wow I need to wrap this up... but as much as it might hurt, date him for a little while longer. Show him what you're good at, make him realize what an awesome girl you are, and then make yourself a little scarce. This isn't playing games. Sometimes the old saying is true, you don't know what you have until it's gone....so don't be gone, just be a little harder to reach. Don't be a bitch to him, don't act like you're not interested, just try not to be so readily available whenever he wants to do something.
Good luck!!!!