<human>: Could you distill the essence of the text into 1-3 sentences?

So, I recently met this guy I have pretty incredible chemistry with. I'm 21 and he's 22, it's only been about 3 weeks (I KNOW, trust me)--I've always been a relationship type of person, which is why it's important to me whether we'll eventually date or not. We both admitted we liked each other, and conversation, spending time together, etc felt easy from the get-go. We've been hanging out about 3 times a week, and yes we're both college undergrads, both working this summer, and live about 30 minutes away from each other. Sometimes we do just hang out at his place, watch a movie, and mess around a bit (no sex, but other things) and other times, we'll go out and grab dinner, go for walks, watch a movie at the theater, go out to the club, etc. He did introduce me to his 2 best friends last week and we all hung out once, and he does  initiate texting almost every day. I was really wondering though, because I tend to be the one that suggests that we hang out. I may be reading into this too much, but he did have to cancel a date we had planned yesterday for work, which I completely understand. He didn't really seem to make an effort at the time to reschedule though; he had told me last week he had Friday off, so I suggested Friday, but he said he was busy because he had lunch planned with a friend as well as a party to attend at night. Again, this might just be me over-thinking things and expecting too much, but I was a little disappointed to see he didn't really suggest another day or possibly ask if I want to be his date to the party...
My question is just this: what are signs that will tell me he's serious about a possible relationship as opposed to just a hookup?
<bot>: Met guy, we like each other, was curious as to what signs guys give about considering you a dateable prospect or a hookup