#18, #17 Really like both of these - colors are perfect and the graphic is interesting. We definitely like the academia-themed graphics, rather than a more athletic themed whistle graphic. Would be very interested in seeing any other graphic representations of academia from artists.
#17, although this is one of the most eye-catching and visually pleasing designs, we do not feel that it will translate well to black and white when people print it from a website. The primary use for the logo will be online; however we will use it on electronic documents that will later be printed by the end user, so must consider how it will look in black/white and low-resolution.