Hmmm. I'm honestly surprised they decided to animate this small arc after all. They did skip it last season in order to enter they Hyoka arc.
Answering both of you, Kraco and Archie, about the particular flashbacks we saw, specially when Mikoto came into scene... this episode is called August 31st. Its the last day of summer vacation. Meaning this takes place before the Hyoka arc (which takes place on September 1st)
And not just that.
This episode takes place at the same time Accelerator is saving Last Order. The very same night. And to end it... it takes place a few hours after Touma fought the fake-Mitsuki-Aztec-magician that has a crush on Mikoto, that is why she blushed so much this time around. She still had fresh on her mind whatever Touma said (since we never learnt it)
This story was the weakest of the 3 small stories that take place on August 31st, so I wasn't surprised it was skipped last time. Even so... the manga did present this in the actual timeline before Hyoka.
My guess is that they decided they wanted to animate everything after all... and to start the season with an episode semi-focused on Index.
Regarding the opening. Im quite happy to see Accelerator between the 'main' characters this time around. I hope to see more of the bastard. And like I said before... wow at the number of characters.
Anyone surprised the ending shows Mikoto first? And even between Touma and Index?
The epilogue with Kanzaki and Tsuchimikado was awesome. Im very interested on why Kanzaki is acting against the English.