The gal or guy pushing the shutter button determines if a camera is amateur
or professional.

No doubt that almost all professionals use DSLRs as their main bodies, but
some use higher-end compacts (point and shoots) as backups. Some use those
super-zooms.

"Prosumer" is a messy tag that will never be agreed upon as to what the hell
it exactly means. A "bridge camera" is another fuzzy term.

Just define your goals and do your homework and forget about the stupid
labels.