Maya = the only firms I know that use it are the blob gang (there's just no good reason to use it over more compatible and established software)

Rhino = seems to be growing in popularity, no doubt because of it's cost, but not many will use it (see above)

Lightwave = don't know of any firms that use it (see above)

These are probably the wrong programs to learn, as far as being assets when the time for employment comes around. Max/Viz and FormZ are the dominant ones, by far. FormZ will probably edge out Max/Viz for the regular firms that don't have specialized 3D departments.
I'd switch to those, if your main concern is to learn something that is used everywhere (but for school, anything is fine, although I'd want it to help me get a job, if I were you). I am sure there are firms out there using almost everything, but I'd say 95% use FormZ and/or Max/Viz.

really?? i thought FORM Z was also for the blob gang... anyways yes i know 3d MAX/VIZ already thats why i was interested in seeing what else should i learn...

so far: intermediate level of RHINO and good level of MAX/VIZ....and mmhh oh yeah i saw once Future systems (those british guys) asking for a LIGHTWAVE modeller, so i thought it was more popular....

ok yeah i dont worry bout school...everything will do for school...im more worried for job chances later, and any advantage i would have in a proffessional field...

FormZ was used at every firm that I've worked at and every firm that my friends have worked at (to my knowledge). Max was used occasionally as a renderer, but there was only a handful of licenses for hundreds of employees.
FormZ is the fastest modeler for regular architecture that I've used (I don't know Rhino, but Rhino is nurbs based). Rhino and Maya are great for the surface/blobby things (Greg Lynn, Rashid, and most of the other blobbers have been using it before it was Maya). Max is just as capable, too, for the curvy stuff.

For jobs, you can't go wrong with FormZ. It's made for architecture/industrial design, so it's easier to do the things most firms need. Max/Maya (and Viz to some degree) are aimed more at the Hollywood and video game crowds. I find Max and Maya to be quite cumbersome to model regular buildings in, but you can do it and many like it.

Lightwave is kind of a unique player. I personally don't know of any firms that use it, but I also don't know of any cons to using it (it's pretty cheap compared to Max).

Yo Trace...found half of the question here:

http://www.archinect.com/forum/threads.php?id=1051_0_15_0_C

I wish Rhino would run on Apple not in virtual PC. It is so much cheaper and produces things at the same quality as I get with form Z, if not better.

I've been tempted to give it a go. Lotsa people love it, but I am fast with FormZ. We'll have to see, it's growing in popularity and I know Brazil has is now compatible with it, which is HUGE.

http://www.splutterfish.com/sf/sf_gen_page.php3?printer=1&page=press/SplutterFish_and_McNeel

If I wasn't already a Final Render user, that'd be tempting. If only you could animate in it.

Still, though, those firms that were listed were progressive, not the norm. If jobs are your concern, I'd at least learn FormZ's basics, it ain't hard (a hell of a lot easier than Max or Maya).

Soon it won't matter as much as Final Render and Vray will have standalone renderers, so you will be able to build in anything you want.
Sketchup is another that is growing in popularity for it's ease of use, but it's almost the opposite of Rhino.

One other thing to mention is the plugins that go with Max, like Dreamscape, which I am beginning to learn and is pretty awesome. All depends on what you want out of software, but they are all good.