If there’s one upside to summer ending (it feels dirty even saying that), it’s what kicks off tonight: a new NFL season!

In what’s become a tradition over the past several years, the defending champion Steelers will host the Tennessee Titans in a special Thursday game — and there’s little love lost between these two teams. Last year, Tennessee had the NFL’s best regular season record, and during a December win over Pittsburgh they let their distaste for Steel-town be known. Of course, that turned out to be Pittsburgh’s final loss, as they crushed Tennessee in January en route to their sixth Super Bowl win.

But how do the teams stack up on eBay? Well, that’s where the Terapeak NFL Index comes in:

Now, pitting almost any team against Pittsburgh is unfair — they’re one of the most decorated franchises in pro sports, and have long been among the NFL’s top merchandise-sellers. So it should come as no surprise that only the Dallas Cowboys have made more eBay revenue  over the past 30 days, or that Pittsburgh has sold more than twice as many items (17,717) as the next-best-selling AFC team (Miami, with 7,665).

But give the Titans some credit: their average price on eBay ($91.76) is higher than all other 31 NFL teams. (Though only the lowly Bengals have sold fewer items amongst AFC teams.)

Following Dallas and Pittsburgh to round out the Total Sales top 10: Chicago, Minnesota, Green Bay, NY Giants, Philadelphia, Washington, Baltimore and Cleveland… Not a lot of south on that list, hey?

Just like last year, we’ll be blogging about the index as the season marches on, but save the link for yourself if you’re selling anything sports-related. Also of interest: the Terapeak NHL index… hockey’s just around the corner, too!

The NHL’s trade deadline looms next Wednesday, which means the drive to the playoffs has officially begun. In this coming week, teams will have one last chance to shuffle their rosters and try to reposition themselves for a long Stanley Cup playoffs run… Which really isn’t all that different from preparing for a selling season on eBay!

At the beginning of October, we reported that the top-three-selling NHL teams on eBay were Detroit, Pittsburgh and Montreal, followed by Buffalo and then the rest of the league’s “Original 6″ teams (Chicago, Toronto, NY Rangers, Boston). So what’s changed since then? Well, not a whole lot. Have a look at our NHL index here, or its companion widget below:

Perhaps the two most noticeable declines are Montreal and Toronto, both of whom have underperformed on the real ice as well this year. Boston, with a huge lead in the Eastern Conference through 62 games, has seen probably the biggest surge in the eBay standings, followed by Washington and Philadelphia (two more teams having excellent seasons — funny how that works, huh?).

In the Western Conference, the NHL’s best team so far this year, San Jose, still has a ways to go to catch defending champion Detroit in terms of eBay sales — but considering how poised the Sharks look for a long playoff run and possible championship, they might just be the best investment out there!