What in the world happened today?

So today the Astros claimed St. Louis 2B/3B Ryan Jackson off waivers, outrighting J.D. Martinez from the 40-Man roster. Who is this guy?

Jackson was the Cardinals' 5th Round pick in 2009 (yep, a Luhnow draftee) and made his ML debut in 2012. He went 2x17 in 13 games (18 PAs) for the Cardinals in 2012, and 0x7 in seven games for St. Louis in 2013, giving him a robust -42 OPS+ in a ridiculously small sample size.

In five minor-league seasons, Jackson has hit a combined .270/.339/.365 with just 378 strikeouts in 2417 PAs (565 games). In two seasons at Triple-A Memphis, he hit .275/.343/.371 with 166K:95BB in 238 games. So: good OBP, not much in the way of slugging, and since he spent most of his defensive time at shortstop in 2013 (72 games at short; 32 games at third) he may provide some insurance should Jonathan Villar get injured/suck/not be ready for 2014.

Cards Conclave had this to say about his potential 2014 season:
With shortstop being such a focus this offseason, I expect Jackson will either be a throw-in to a deal or will be outright released to make room on the 40-man roster.  Even if he somehow stays in the system, he’ll do a lot more time in Memphis.

In addition, Jake Elmore was claimed off waivers by the Chicago White Sox (.242/.313/.325 in 136 PAs). Baseball America's J.J. Cooper said that Jackson basically replaced Jake Elmore in the infield, which is a "definite upgrade."

Meanwhile, J.D. Martinez has been tearing the cover off the ball in ten games (I know, it's just ten games) for Carolina in the Venezuelan Winter League so far, hitting .293/.341/.610 with four homers and a double (11K:3BB) in 41 at-bats. I guess I'm more surprised that Eric Thames was left on the 40-Man roster, and Martinez was the corresponding roster move.

And not only that, but the John Ely Era is over, with the Astros releasing him. Ely was acquired on December 19, 2012 in a trade with the Dodgers involving Rob Rasmussen (whom the Astros acquired from the Marlins in the Carlos Lee trade), and needed Tommy John surgery after one appearance for OKC.

The Astros tweeted that there could be more roster transactions tomorrow, in advance of the Rule 5 draft, and the Astros' 40-Man roster currently stands at 34.