A cat cold is pretty much what is called a URI Upper Resperatory Infection, which is really the same name for what us humans get in some forms, we just call it a cold more often then not.
To the best of my knowledge, you can not get a cats "cold" and you can not transfer something like your sniffles or sinus infection or cough to your cat.
At the cat shelter where I volunteer, we are warned that respiratory infections are one of the things that cats can have that are contagious. I have no formal kitty training, so I'm not sure, but that's what they say there.
chix: contagious yes, very much so, but... to other cats.
I used to spend my time at a humane society, and they had their signs and measures to prevent spreading desease from cat to cat, a URI being one of their top priorities.
At this place... if a uri spred to to many cats... at one time... and quaranteen/meds for a few didn't help... they would put them all down.
There would often be times I would come into work and the cat section would be closed down, all dark, they were all gone.
Very much sad.