We care about every kind of proc. It depends on what spec you're playing as to determine which may be more important to you. But every spec has at least 1 dot and will want to game pandemic with procs and such.
We do indeed care about haste procs. I would recommend you getting the affdots addon. It will track your dots, but more importantly it will tell you the strength of your current dots vs. the buffs you have on. Its very beneficial.
It can be downloaded here: http://www.curse.com/addons/wow/affdots