Instead of living with my H.S. buddy, I went the random route. I was going to live with him, but we couldn't agree on what style dorm we wanted. He wanted corridor where you just live with one other person, and I really wanted to live in a suite with 4 other people but a semi private bathroom that you didn't have to share with the floor.
I ended up seeing my friend from H.S. every so often at parties and the bars and in classes (we shared the same major) but he got his own group, and I got mine. I was lucky that I ended up living with 5 of those 6 guys through my 4 years in college. We hated one guy, but he moved out of the suite after 1 semester. I had a great experience with my roommate, and we lived with each other again sophomore year and moved into the same house for the final two years.
And now, a year after I've graduated, I still see that friend from HS every few weeks. Honestly, I can see the merits of doing both. Whatever you do - be sure to expand outward and make a ton of friends. College will be like no other time of your life, so don't take it for granted.