From my research and observation, giclee is some process thought up in france. I have no idea how it compares to what is being sold as giclee canvas prints by many labs.
Realistically, I've seen 2 processes - one is to take a regular print and remove the back part of the paper to thin it. It is then glued and pressed onto canvas (or some synthetic equivalent, or canvas textured masonite). It is the same as a print as far as UV and what not. You can't get a 'gallery wrap' where the image wraps around the stretcher bars as it will damage the print.
The second is inkjet on canvas (or some synthetic canvas textured material). This is often sold as 'giclee' but some places also call it inkjet...give it a french name and charge more I suppose
These folks
Go To Canvas - Photos or Art Professionally printed onto Canvas at reasonable prices! admit to using inkjet, but then the cost/seal the final print - and it's pretty damned durable based on the sample I got that I've abused. I've not tried the sun fade test, but I suppose since they claim its UV coated it is. It's some of the best I've seen and they offer a variety of options - canvas 'loose', stretched for framing, gallery wrap and some framed sizes. They have a commercial/pro photog division.