Rotating queue? Good idea. Only on weekend? Bad idea.
Being a responsible adult means holding down a job, and holding down a job generally means working on weekends.
No permanent-rotating queue, whatever. Why not an extra two days on either end of the weekend?
Why not do it all week long like WoW does with their bonus events system? Because it's new and still in the works. WoW's started out as only weekends, then expanded to 5 days a week, and is now all week long. Riot doesn't know how much people will play it, yet, how many people will play it, how it'll effect queue times on other modes, if it'll be like Dominion, etc. They need more information if they want to release it for extended time periods. Just remember, not every release was planned, meaning it's possible they do extend it in the future.
