The actual issue has to do with how Gmail stores contact images. It has been around for a few years, and has affected users of a wide variety of smartphones of various platforms and screen resolutions. Apparently, Gmail converts higher resolution images to a lower resolution, and those lower res images will sometimes replace the higher resolution images on your phone when it syncs with Gmail. On my Pre (and now my EVO), I just loaded a set of high resolution photos, and updated my contact images on my phone, and that did the trick. Unfortunately, I have to do this each time I doctored my Pre (to clean up my mess before major updates). Very annoying, to say the least. Hopefully, Google will someday bump up the size of their contact images.