Well I just got back from the show. Something interesting I noticed, they've changed the dance positions for Namida no Iro ever so slightly. Maimi is now consistently the front for the whole song, Airi's been bumped back to Maimi's second position for the parts she was there.
I have to say, on the one hand this concert disappointed me a little. I was expecting a lot more interaction between the two groups, and maybe even some song swapping. Instead, there was even less than you see at a H!P concert, they pretty much stuck to their own songs, sang as a whole group for about three songs the whole concert (that is, the full duration of the song together, not 10 seconds and then running off) and only mixed up the girls in the middle. What a wasted opportunity.
But then, Berryz Kamen and Cutie Rangers at the end entirely made it all worthwhile