It's that time again ...

UFC champions Anderson Silva and Sean Sherk bucked the 2007 upset trend to retain their titles at UFC 73: "Stacked," wreaking the most havoc to the contenders in their respective divisions for this edition of UFCmania rankings.

However, all the activity in June and July -- four events total -- has distinguished the top two contenders in the middleweight and lightweight divisions.

Yep, Rich Franklin and BJ Penn have once again locked up title shots and will challenge Silva and Sherk, respectively, later on this year.

The decisions these days are a lot harder because so many good fighters are in action so often. It was a little easier way back when to determine who belongs on this list.

Right now, the heavyweight, welterweight and lightweight divisions are loaded with world class talent. Light heavyweight seems a bit top heavy, and well, does it really matter at 185?

Silva looks unstoppable.

At any rate, before we get to the rankings I want to again thank our loyal panel of overt and covert contributors, including Steve Seivert at the Houston Chronicle, Dave Doyle at Yahoo!Sports.com, Pramit Mohapatra at the Baltimore Sun (and MMAMadness.com), Miguel Lopez at the Long Beach Press-Telegram, and Luke Thomas from BloodyElbow.com.

These fellas keep us honest. Naturally, the UFCmania.com team also pitched in.

Enjoy ... and remember to let us know what you think.

To see the latest UFCmania.com rankings for July 2007 click here.