I recently was able to sit in on a jurying process for an art club. It was a real privilege and I both enjoyed the experience and learned from it. (See the last entry in "Dealing With Rejection" in this Tech Talk Section). The jurors viewed all of the slides that were sent in for consideration. Several of them were obviously taken by the artist who apparently hadn't read some of the information available both in magazines and on line about how best to take photos of your artwork.
All of the jurors commented that this made it much more difficult to make a good decision based on the art because the photo got in the way.

Related to frame or no frame.... Examples of artwork both framed and not framed were submitted. That didn't seem to affect the jurors as much as the quality of the artwork and the quality of the photo of the artwork, but I know most professionals photograph the work without the frame.  

Scott Burdick has a whole video about photographing your artwork and there's a little description on a "how to" section of the Masterpiece Artist Canvas website.