You're right because I forgot about that champion from the Power conference that is the American .... LAST YEAR.
If you consider Power Teams those that play in the big conferences (Pac 10, Big 12, Big 10, SEC, ACC and the Big East-which may or may not keep that designation), only UConn last year (and they really shouldn't count as they recruited all their players as a Big East team), and UNLV in 1990 have won it since 1987. Before that Louisville in 1980 and 1986, and Marquette in 1977 are it since 1966.
I would submit that UConn, UNLV, Louisville and Marquette were all considered top flight or "power" programs and annual threats the years they won. You have to go back to Texas Western in 1966 to find a real "little guy" champion.
So I don't think things have changed that much. Right now there a few schools like Kentucky and Duke that enjoy a real competitive advantage because their coaches are so popular with the cream of the high school crop. That will change over time as the coaches change. All you can do is tip your hat to those guys and try to hire or develop one of those coaches for yourself.
Finally, Wisconsin will always be good as long as Bo Ryan is coaching them.
