It's not selling as well as "The Gilmore Girls" (which I think was released the same day) but it's doing okay. It was #78 on the charts the week after its release. Not spectacular, but seemingly it's moving enough units to warrant more seasons released.

That seems about right. Gilmore Girls is still on the air and people have it fresh in their minds, while Party of Five has been off the air for I think almost 4 years. But the nice thing is that Columbia and Warner Brothers knew when they released the box sets that they were only a number of interested buyers for the release, and Party of Five is doing well (for what they were expecting)... But Gilmore Girls is exploding (warner was not expecting the sale they got with this release, which explains the very limited features)...