Slowey turned in an up-and-down season in 2010. While his final ERA of 4.45 wasn't spectacular, he had his moments and until a 6 earned run disaster in just an inning and two thirds right before the end of the season, his ERA was just 4.18. All told however, 2010 was a solid year for Slowey. Despite missing some time with injury, he made 28 starts, a career high, and posted a very solid 3.98 FIP - better than that of Carl Pavano.
Slowey misses an average number of bats (good), and perhaps even just a tick above average number, while walking essentially no one (great), and giving up fly balls in droves (very bad). Combined, that's allowed him to post very good FIP marks ever since his brief introduction as a rookie. His one really poor season, 2009, was largely the result of a horrendous BABIP mark of .345.
Slowey won't give you a ton of innings because as fans of the Twins are well aware, he has an annoying tendency to allow hitters to routinely run the count deep and drive his pitch counts up very quickly. That's largely because he lacks a true put-away pitch and refuses to give in to hitters. However, he's not by any means a bad pitcher - he just isn't an ideal one.
What remains to be seen is what role Slowey will be deployed in. He, along with Brian Duensing are the presumptive favorites to open the season in the bullpen now that Pavano's signing has left the team with six men for five rotation spots. However the teams management is saying all the right things for now, stating that they're happy to have a surplus as will allow the situation to work itself out in spring training.