When to list jobs on a resume

Hey there, I'm a recent graduate with my RN license. I constantly try to rehash my resumes from advice on this forum and have bought a couple resume books. I recently started working at an SNF/LTC facility (started last month) because I am aware of the hardship for new grads to get into hospitals. I am still actively looking to work in a hospital but took the LTC position because in this economy having a job you may not like is better than not having a job.

Anyway, I was wondering when it would be appropriate to list the LTC on my resume when applying. I hear different things from people telling me to do it right away and others saying to wait six months to a year. Any ideas? I am also there per diem if that affects it (I work part-time to full-time hours).

Thanks ahead of time!