We'll be updating this throughout the day, so keep checking back.
Jon Heyman says the Astros moved on Porter before the Marlins could:
"The affable, energetic Porter is well regarded. In Washington, Porter managed to be liked by both GM Mike Rizzo and previous Nationals manager Jim Riggleman even though Rizzo and Riggleman for the most part seemed to have separate reporters (the ones who backed Rizzo remain). Porter's Nationals ties aided him in his chances with the Astros, as Astros first-base coach Dan Radison, who is a close confidant of new Astros GM Jeff Luhnow, was on the Nationals coaching staff under Riggleman."
The Nats Blog:
Porter has worked
closely with Nats outfielders and baserunners during his tenure with
the team. In spring training 2011, he had outfielders carry footballs
while tracking down fly balls to help them close on balls. It was a fun
drill, but also one to make a point to his guys. He's well respected in
baseball, and the Nats will certainly miss his presence next season.
MASN's Dan Kolko:
Once Johnson does step aside, the Nats hope to replace him with an
in-house option. Porter was considered one of the names towards the top
of the list, but now, that list contains the names of bench coach Randy
Knorr, first base coach Trent Jewett and Triple-A Syracuse manager Tony
Beasley, among others.
Washington Times:
When Porter interviewed for the Marlins' vacancy at the end of the 2011
season, the Nationals made it clear they would love to keep him but
would not stand in they way of his moving on for a more prominent
position.
Buster Olney:
He's young, upbeat and energetic, and the team can grow with him as it
develops in the years ahead. Plus, the Astros don't have to pay him
much, and he'll be more open to the heavy dose of sabermetric tonic
prescribed by the front office than a lot of more established managers
would be.