"Greek" casts a pop star as a part of Calvin's new storyline

I love Calvin.  I find him to be one of the more interesting gay male characters out there (with all do respect to Kevin & Scotty and Luke & Noah).  His sexuality is never hidden but it is also not the only thing that defines him.  He is a part of main character's storylines (beyond just dressing tips), but he also has strong stories of his own as a secondary character.  He has a boyfriend, and even the boyfriend becomes a part of the main character's storyline -- Michael being bribed by Evan to help a fellow frat brother's grades.  All in all, I love Calvin.

I also love how creator Patrick Sean Smith infuses the whole show with such a queer sensibility.  Whether it is the Women Studies phallus discussion or the tender ways the macho Kapa Tau's treat each other or the way most of the straight guys do not seem to be threatened by a little gayness in their lives.

I particularly like how Heath has continued to be a supporting part of the Kapa Tau house and interacts easily with the straight boys while also enjoying dancing at the gay bar.  Also, I am enjoying how homophobic Dale has been treated as more than just a Bible-thumping stereotype.  People are allowed to see how a person might have religious objections to homosexuality while still not being abusive toward gay folks.  Plus, Dale's admission of his love for cheerleading and his use of nail polish remover were just hilarious.

Greek is possibly the gayest, and one of the funniest, shows on TV.

Okay, let me just say:

I don't think there was ever any risk that Calvin would become a, as you say, "barely there" character. You only have to look at the connections he has on the show.
He is Rusty's best friend. That's Rusty as in the show's MAIN main character. Much of last season was spent exploring the boundaries of their friendship and the difficulties they faced from being in rival fraternities. 
He is the "Little Brother" of Evan Chambers, another important character who, last season, also did much to prove his friendship with Calvin.
He is also the best gay friend of Ashley who, once again, worked to concrete her friendship with Calvin.

Little to no risk, I could safely say... Or something

I really like how the show incorporates very "gay friendly" material into the series. Calvin is a strong character who defys stereotype, and I enjoy where they are taking his storyline!

I have to say I disagree with the above comments. Calvin is defiinitely in danger of becoming a " barely there" character, unless things turn around soon. As one of the posters above said, Calvin has the same relationship to a main character as Ashley does (best friend to the star character), but do you seriously think that Calvin is in any way as prominent as Ashley? Does he get even 10% of the screen time she gets?

And what about Calvin's alleged "relationship" with Michael? He cheats on Michael and Michael disappears completely? Are we even going to get a break up scene?

Even minor characters like Dale and Beaver(!) are getting more screen time than Calvin. He is danger of becoming the dreaded token gay, though I hope this trend will turn around.