As NFL minicamps and spring practices continue, many interesting scenarios are developing around the NFL. Here is a look at five subjects that bear watching:

1. Proliferation of wildcat formation
Rookie wide receiver Percy Harvin already has taken direct snaps during Vikings practices. The Ravens might use more wildcat packages, featuring quarterback Troy Smith in a variety of roles. And we certainly can expect the NFL's masters of the wildcat, the Dolphins, to expand their packages after drafting elusive quarterback Pat White.

"We really didn't scratch the surface last year," Dolphins coach Tony Sparano said. "Truth be told, going into every game, we probably had a total of three (wildcat) plays on the game-plan sheet. That's why I think it's important that we keep our information to ourselves."

Sparano expects more teams to implement the wildcat and hopes his defense will benefit from seeing it frequently during practice.

"We know that other people are going to try and do it, as well," Sparano said. "The more reps our defense can get vs. the wildcat, the better off we feel like we'll be prepared when it happens during the course of the game."

2. Matt Hasselbeck's back
So far, so good for Hasselbeck, who is moving and throwing without pain. Hasselbeck's health clearly is the key to the Seahawks' playoff hopes. They had won four consecutive NFC West titles until last season, when back problems limited Hasselbeck to seven games.

In spring practices, Hasselbeck is bonding with new favorite target T.J. Houshmandzadeh and learning the offensive wrinkles added by new coordinator Greg Knapp.

"It's exciting to watch the cutups of stuff Greg Knapp has done and also how the running game works, how his play-action works, the naked bootleg," Hasselbeck said. "A lot of that stuff we had but we didn't emphasize. Now, it's definitely emphasized."

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The Seahawks have intangibles working for them -- veteran players used to winning, a noisy home stadium and an '09 schedule that includes just five games against playoff teams from last season.

Seattle could be a surprise team in the NFC, but only if Hasselbeck stays healthy.

3. Vince Young's angst
Young, the Titans' backup quarterback, told a TV station that he wants to start in Tennessee or be traded. This sounds like a bigger problem for Young than for the Titans.

Kerry Collins has a new contract and led the Titans to the NFL's best regular-season record (13-3) last season. It is unlikely that coach Jeff Fisher would bench Collins, particularly after some of the drama Young put the Titans through last season.

However, this is the biggest offseason of Young's career. He is only 26 years old, 10 years younger than Collins. With two years left on his contract, Young needs a strong training camp and preseason to show the entire league, not just Fisher, that he still can realize his potential.

It is perfectly fine that Young wants to start. Now, he needs to convince the Titans, or another team, they would be better with him in the lineup instead of on the bench.

4. Brandon Marshall's troubles
One of the league's best wide receivers, Marshall is in the final year of his contract and wants a new deal. Marshall will not be suspended by the league for a March 1 incident. However, he is scheduled to stand trial in Atlanta next week for two counts of misdemeanor battery in an incident involving a former girlfriend. That case will be reviewed separately by commissioner Roger Goodell.

Can Marshall, arrested three times during a 12-month span, avoid further problems? And will he develop the same chemistry with either Kyle Orton or Chris Simms that he enjoyed with Jay Cutler? Stay tuned.

5. The Bills-T.O. honeymoon
Will it last the entire season? And will Terrell Owens' presence help the Bills make the playoffs? The answers will determine whether coach Dick Jauron keeps his job. Jauron says Owens will make the offense more dangerous, especially in the red zone.

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"His reach is a factor, his size is a factor, his ability to screen with his body is a factor," Jauron said. "It does open up the field and opportunities for other people."

The Bills begin a mandatory minicamp Tuesday, and so far, Owens has been a happy camper.

"He's a cool dude," running back Marshawn Lynch said. "I love having him on the team."

Few in Dallas, Philadelphia or San Francisco, however, loved Owens when he left town. We will see if the Bills still love him in January.

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