That move was made due to multiple reasons, one of which being the emergence of second-year WR Mike Wallace. Another was Holmes' extension situation and alleged desire to be paid more than any other receiver in the game.
It's interesting how quickly things change, yet, remain the same, in the NFL.
Now, allegedly, it's Wallace who's seeking the kind of money the Steelers eschewed Holmes for requesting. Holmes situation was different. Due to a four-game suspension for a flunked drug test, Tweets about smoking pot, and incidents in nightclubs, Holmes could be seen as a loose cannon, particularly because he was disgruntled about his lack of contract extension.
Because of all those mitigating factors, the Steelers chose to jettison the tarnished hero to the Jets, who were glad to part with a lower-middle round pick for the talented receiver. At the time, the move was highly criticized, with most suggesting Holmes should have fetched more value in a trade, considering the size of his contract at the time and his obvious talent.
The move was largely made out of protection of the team's chemistry. QB Ben Roethlisberger had found himself in the headlines every day after incidents in Georgia (of which he was never charged with a crime, except by the Court of Public Opinion), and the Steelers decided they didn't need a pouting Holmes playing 12 games for a team he had no intention of playing for beyond the 2010 season.
Needless to say, the trade worked out in Pittsburgh's favor; although Holmes did play well in New York that season. He had a meager six catches for 40 yards against the Steelers in a 22-17 Jets win in Pittsburgh, but in the AFC Championship game that year, Holmes' only production came on a 45-yard touchdown pass after Steelers CB Ike Taylor slipped and fell in coverage before the ball was thrown. The Steelers would go on to win anyway.
Meanwhile, Wallace has only improved, and while critics cite a lack of production in the second half of 2011, he was a monster in the first half of that season, and earned his first Pro Bowl bid as a result.
The offseason contract news surrounding Wallace took another step forward Wednesday, with a report surfacing about Wallace's lack of intention of signing his restricted free agent tender offer from Pittsburgh. Holmes was under contract for another season, and bypassed restricted free agency. There weren't reports of Holmes holding out before he was traded, but it was reported he was unhappy with his contract all the same.
If the Steelers dealt a baggage-laden Holmes, who was still under contract for a relatively low amount of money, what would prevent them from making a similar move with Wallace?
There's precedent, too. In 2007, Miami had given WR Wes Welker a second-round tender in restricted free agency. Both the Patriots and the Vikings were interested in signing Welker, so the Patriots wisely offered their second round pick (which the Dolphins were set to receive if a team signed Welker to an offer sheet) as well as a seventh-round pick. In doing that, they received Welker's rights, meaning they held the right of first refusal over any contract offer the Vikings may have given him.
Perhaps a team won't be willing to sign Wallace to the big money deal he's apparently wanting (Vincent Jackson's contract with Tampa Bay calls for $26 million, and it's reasonable to expect Wallace to use that contract as his main comparable in his negotiations) along with giving up a first-round pick.
But it's not against the rules for the Steelers to trade him for an agreed-upon amount. There are also a few teams with desirable draft picks who could really use a receiver with Wallace's field-stretching ability.
Minnesota has been curiously quiet in free agency. With a good chunk of cap space, and only significant offseason move the signing of local product TE John Carlson (five years, $25 million), it seems odd a team in a vicious stadium battle wouldn't even toe the water for a receiver like Jackson. Outside of Percy Harvin, the Vikings have essentially no real production coming out of that position. The signing of Carlson, along with the development of uber-talented Kyle Rudolph, suggest the Vikings are looking at a vertical attack from in-line players to help open the box for RB Adrian Peterson.
What would open that up even more would be a receiver who can get down the sideline in a hurry.
The Vikings are almost assuredly taking USC LT Matt Kalil with the No. 3 overall pick. They also picked up two other fourth-round picks in compensation for losing DE Ray Edwards and WR Sidney Rice in 2011. While their second-round pick (No. 35) is highly coveted, they have the cap space available to give Wallace the front-loaded contract he probably wants. No receiver likely to be available at 35 has the production Wallace has in the NFL, obviously. Pairing Wallace with two talented pass-catching tight ends and an excellent pass-protecting left tackle would give the Vikings an actual chance to compete in a division where, to put it mildy, they're severely out-gunned in terms of offensive firepower (Rodgers, Cutler, Stafford and...Ponder?).
The Steelers wouldn't likely be willing to part with Wallace for just one pick, however. Losing him would mean they'd be down to just three receivers on their roster - Antonio Brown, Emmanuel Sanders and the newly signed Jerricho Cotchery. While teams cannot trade compensatory picks, they still have 10 overall picks currently to rebuild a sadly depleted roster. Giving up the valuable second-round pick, essentially, for Wallace would give them the skill position player they need, and the additional fourth round pick could be made up for with a Steelers' 6th and 7th round pick (no team can have more than 10 picks, and both teams currently have 10 picks).
The question is whether the Vikings are ok with the massive price difference between the second round pick they would otherwise draft, and Wallace. No one said talent is cheap, though.
Looking at it as objectively as a Steelers writer who lives in Minnesota can, it works well for different reasons for both sides. The Steelers have already shown once they're willing to depart with a talented receiver with a year left on his deal for a fifth round pick (mostly because they're confident they can turn that 5th round pick into a starting CB and Antonio Brown, who, incidentally also made the Pro Bowl, when Holmes did not). Getting two higher picks than what they're giving up, plus, saving the cap room of Wallace's contract this year, and the massive increase it would take next year with either a long-term deal or a franchise tag, could be the best move the team could make, given the circumstances.