Thoughts on... everything.
Pros:
+1: The girl's pose is cool.
+1: Two rivals sounds good. I just hope they both recur more often than Brendan/May and Wally.
+1: I have no idea what one would need a touch screen calculator for, but I'm happy to see it. Maybe to select the number of items being withdrawn or deposited into a PC, or something like that.
+2: The Diamond legendary looks like a futuristic combination of the three legendary beasts, and the Pearl legendary looks like a futuristic Groudon. In spite of that, I like them both. I do wish, however, that they'd finally taken the opportunity to introduce a Light type (the only one I want added), because if any two Pokemon ever looked like candidates for Dark and Light counterparts, it's these two.
+2: The menus, in general look better, cleaner, and less cluttered. This is largely just due to having more space to work with.
+7: This is probably the first time I've liked the majority of the new Pokemon designs that have been revealed. I didn't like the new G/S/C ones that we saw before the release of the games, and liked the R/S/E ones even less, but I like the music note bird, I like Lucario, I like Weavile and the water weasel.
+8: With the others, I may not like their designs, but their abilities or attacks are great. People have been begging for a Poison/Dark type a long time because of the defensive synergy going on there (Poison is weak to Psychic but Dark is immune, Dark is weak to Bug and Fighting but Poison is resistant, leaving only Ground as a weakness), and we finally have a Pick Up Pokemon who's not a Normal type or Phanpy. Special mention to that "Cross Poison" move also, since Poison in general has needed better attacks.
+30: Cherimu (the Sakura flower Pokemon) gets its own section of my comments because from the info on Serebii.net, it looks like we've got a move that's almost definitely going to catapult itself into a top-tier slot: Trouble Seed, changing the enemy's ability temporarily to Insomnia. Besides the obvious use of blocking currently-overused stuff like Suicune and Snorlax from being able to Rest (a move that's needed more counter-balancing since day one of R/B/Y), you could get rid of, say, Volt Absorb on Lanturn (goes from absorbing Electric to taking normal damage from it) or you could get rid of Levitate on Weezing and make it go from immunity to a 2x weakness, or so on. This is fantastic. Cherimu looks like a weak Pokemon, though (maybe a Jumpluff sort), but I'm assuming that other Pokemon will have this same move.
+30: Wi-Fi will make a lot of people happy.
Cons:
-3: I'm a little disappointed with the touch screen controls on the bottom. I mean, I'm glad they moved it to the bottom, but there are two things I think they could've done much better: 1) made it prettier, because, man, is that orange-ish interface for the bag ever hideous (that's just the bag menu, I don't know about the others), and 2) why didn't they move the "[Pokemon] used [attack]!" announcement down to the bottom screen as well? We could have had more room for sprites and attack animations in the top. (I turn off animations after a while, but still, they're interesting for at least a bit.)
-2: Team Galaxy. Let me start by saying that I have no problem with always fighting an evil team. That's the classic formula; changing that would be like not fighting evil robots in Mega Man, or not fighting Dracula in Castlevania, or not fighting Bowser in Mario, or so on. I want to fight an evil team of Pokemon gangsters. It's just that the theme of this particular team seems unappealing to me. Partially because it just seems like a renamed Team Rocket, partially because it's only recently that we learned about Super Mario Galaxy, partially because now I don't get to see the evil females' legs.
Potentially -1: I like Cherimu's new move, as I said above, but the ability, depending on how it works, seems to be further tilting the metagame in favor of Sunny Day and Groudon as opposed to the already-shafted Rain Dance and Kyogre. To power up not only itself, but also all of its teammates when Sunny Day is in effect? Yeesh, I know Grass-types needed to be improved, but not necessarily to this degree. ...Again, though, it depends on exactly what "powering up" the whole team entails. If it's something small, it might not be broken.