"Google is a step in the long march to better search. Yes, Google's scheme yields fantastic results. But the Web is inexorably dynamic. During the next five years, it will move from containing primarily file-based content (HTML pages) to containing more executable content (e.g., online gaming or new structure imposed by Web services such as XML). When that happens, the usefulness of link-based search will wane. Simply stated, Google is very much of the times, with no advantage in the more structured, executable Internet that lies ahead."
Over at CNet, Forrester Research founder George Colony has a go at putting the Google IPO into some sort of perspective.