I really didn't think they could come back from their midseason slump to even compete for playoff contention, let alone clinch the NL wild card. At one point, the Astros were 4 games below .500 and appeared to be on their way to the NL Central cellar. However, since August 15th the Astros have clawed their way back with an amazing 36-10 record, and the payoff for them is a postseason berth (they got some help from the Chicago Cubs, of course, who took themselves out of playoff contention with an impressive late-season disappearing act).
Of course, now the 'Stros, who have never won a playoff series, get to face the evil Atlanta Braves, who OWN the Astros in the postseason. I can tell you right now how this is going to turn out. I'll be surprised, in fact, if the Braves don't sweep.
Even though the Astros will be knocked out in the first round of the playoffs like they always are, they nevertheless deserve credit for the way they bounced back from an abysmal June and July to make the postseason. It really was enjoyable to watch.
(Retroblogged on August 23, 2015. Of course, the Astros didn't get swept by the Braves. They actually beat them!)