If anyone was worried that the writers for Supernatural would have little time to tell some side stories this season, they have nothing to fear. This episode had almost nothing to do with the overall season arc or the troubled relationship between the Brothers Winchester, and could almost have taken place at any time in the series' run. If it hadn't been for the exploration of Bobby's circumstance, it would have felt completely divorced from the ongoing crisis.
Not that I blame them for taking the time to delve into Bobby's depression. I's been covered tangentially since the beginning of the season, but now it factors into the story a little more directly. Bobby's psychological wounds aren't healing, and I'm not sure this situation really did very much to change that fact. I'm left to wonder if Bobby is going to recover or be forced to come to terms with his new situation. As long as the writers keep exploring it, I think either direction would be worthwhile.
The idea of a 900-year-old card shark witch certainly capitalizes on the popularity of televised poker, but it does rely on a bit of cliche. As usual, the most experienced players are the ones who lose, and the rookie walks in and manages to buck the odds and win the pot. It's about as predictable as it gets, especially when one would expect a player with Patrick's kind of expertise to see through Sam's facade without a second glance.
Given the predictability of the plot (which was only partially saved by the revelation that Patrick's partner wanted to help the Winchesters), it all comes down to the emotional core of the character development. It's not surprising that Dean would put it all on the line for Bobby. Bobby is their father figure, and Dean definitely has a host of lingering daddy issues. He couldn't prevent Bobby's injury, and he couldn't prevent John's death, so why not make up for both at the same time?
And of course Sam would put anything on the line for Bobby and Dean, even if he started with the notion that he would simply have to keep playing long enough for the spell to be cast. Sam may have been forced to keep playing to the bitter end, but he was more than ready to leave the table and forfeit those years if it meant having a chance to save Dean. It just goes to show, once again, that the Brothers Winchester will sacrifice anything for each other, no matter what else has passed between them.
All in all, it was a nice, solid stand-alone episode. It was a bit too predictable to be among the best of the season, but it did everything it needed to do and continued to focus, despite the high concept ideas, on the characters.