I have a pair of these also. I wear them most of the day in the office. The noise canceling feature is great, but I also can't emphasize the importance of the "over-the-ear" ear cups vs. "on-the-ear" enough. Over-the-ear makes a huge difference if you are looking for isolation.
EDIT: forgot to mention one minor annoyance I have with over-the-ear headphones is how some ear cups fit over my glasses. With these Bose it's not much of an issue since the ear cups are soft enough, but has been much more annoying with other headphones. Something to be aware of, at least.
The glasses angle is something that I had not considered. The QC15s fit nice and snug around your entire ear (not in an uncomfortable way) so glasses could potentially be an issue. They are fairly soft, though, so I suppose it could be worse.
EDIT: forgot to mention one minor annoyance I have with over-the-ear headphones is how some ear cups fit over my glasses. With these Bose it's not much of an issue since the ear cups are soft enough, but has been much more annoying with other headphones. Something to be aware of, at least.