Comment 6 for bug 693903

I think the little red X icons in the corners of every window (whence the window is "deleted") are a pretty big clue that this shouldn't be used. In Firefox, there is no "delete" concept for a web page, so they are able to use it without concern for alternative meanings.

Whilst the trash bin is an improvement for experienced users (at least you can figure it out), its lack of prominence is still an issue. Also, now the trash bin and the trash itself are both used, and right next to each other. Confusing for newer users. Delete is probably used in the order of hundreds of times more than cancel, so should easily get priority if there is "competition" for a visual cue. In fact, I have probably never used cancel in my life in a mail client. I would have to think about it to figure out why it's even there at all.