I was bipolar NOS for two years. My pdoc just didn't want to be pinned down, I think. Which meant I didn't take it seriously enough, at least not until the meds got serious (two antipsychotics and a crapload of Lamictal). Even so, I was shocked when I was diagnosed with bipolar 1 and had it confirmed while I was in the hospital. I guess my manias are bad enough that they rise to that level, although it doesn't seem like it to me (gotta love denial). In the end, the label doesn't matter as much as the treatment, which is pretty much the same whatever kind of BP one is dx'd with.