Buddypress: okay on a subdomain?

I believe I read somewhere on your wonderful site that Buddypress is usually installed on the main domain of a multisite.

I run an online magazine, but also want to offer readers a Facebook style forum via Buddypress (and wpmu social theme) ...

Is it okay to run BP on a subdomain? Is there any reason a main domain wp magazine and subdomain bp forum won't be good "buddies"?

thanks.