GIVN—I remember looking into this a while ago (maybe the situation has changed since then), and claims were made that GIVN's capsule might miss a lot of polyps compared to a colonoscopy because - it might be pointing in the wrong direction as it passed by, or the camera might be obscured, etc.
Yes, the technology has improved. The colon product referred to in this thread is the second generation and is called PillCam Colon II.