Will per diem count?

Yes it will count towards experience, and there is no real rule that says a new grad has to have a year experience in med-surg. so good luck in whatever you decide.

I graduated from RN school in May and started on a ortho/neuro/med/surg overflow floor. I love what I'm learning, I loved my orientation and I love my co-workers. Recently the floor started taking on more med/surg and observation patients and we've basically turned into to med/surg/obervation with a few ortho/neuro. It's gone from busy and manageable to "Oh my God it's already midnight and nothing is done." I've gone from having one or two med/surg/observation patients to weeks where I have no ortho patients at all. We are slammed with patients and I'm frequently asked to take on another patient because "Someone needs to have six patients and everyone else is too busy." This is not the floor I wanted to work on when I applied. I can't take time with my patients like I used to before we took on med/surge/observation.

Recently, I've been thinking about going back to the unit I worked on as an LVN. The problem is that it's not a med/surg unit but a sub-acute unit.

I've always been told that a nurse needs to spend one year on med/surge and s/he "can go anywhere." I've only been on my floor for six months. If I take a position on my old unit and work per diem on a med/surg unit will that count? Or will it hinder my chance of transferring later on in my carrier?

I think it's something that has always been advised, to do med-surg for a year, but I don't think there is any real reason why...especially if you don't want to stay in that area. Why suffer? All your work hours will count towards experience. I would advise to go where you enjoy your job, not where you hate it.