Sorry, my Oz-fixation is clearly out of hand. So here we are in season 3 and Seth moves from "Guest Starring Seth Green" to being a featured regular cast member. The buzz I get from seeing him up there with the big guns is tempered by knowing that this was the beginning of the end for Oz...

Here's what Seth said (from "Ask Seth" on his website)...

My character was conceived as a recurring character and by making me a regular, all of my time was dedicated to working on the show in scenes where my character seemed to be shoehorned into an inappropriate place so that I was regularly featured. I began having other opportunities and working on a show five days a week, 12-14 hours a day, in scene with 10 people, waiting for hours to say a line like "I think Buffy's right," precluded me from taking advantage of them. — Seth