Talk to a Browns fan in July, and he's giddy over the Charlie Frye/Braylon Edwards connection, gabbing about Joe Thomas' work ethic, and insisting that with LeCharles Bentley back in the fold — this is Cleveland's breakout season. Raiders fans? Despite a 2-14 season last year, a super young offense, a rookie coach, and new starters at basically every offensive skill position, the inhabitants of the Black Hole are seriously talking about the playoffs. Texans fans love the Schaub and Green moves, Lions die-hards are giddy over Year 2 of the Martz/Marinelli era, and even Dolphins fans are smiling.

And isn't that the beauty of training-camp season? Reports leak of seventh-round picks making phenomenal grabs in traffic during a July mini-camp and you think you've got the next Marques Colston suiting up for your team. Three weeks later, the guy's an August cut and never heard from again. Rookies battle veterans in the heat, coaches spit their venom from the sidelines, and undrafted cats from small schools make unexpected runs at roster spots not intended for them.

For all the dog fighting, strip-club shootouts and Vegas casino slapfests in the news over the off-season, the NFL can finally get back to its bread and butter this week — actual football.

The fans have been salivating for it.

Trust me, so has the media.

And on the eve of training camps opening across the country, there's unbridled optimism from coast to coast.

But what fan bases should be a little worried? Where are the biggest question marks? Here are 10 trouble spots worth keeping a careful eye on throughout the training-camp season:

1. Minnesota Vikings quarterbacks....