I really like the ease of trading, but why can't I trade Pokemon that have HMs?
The same reason you can't delete HMs at will. You could leave yourself stranded in your previous game.
And why did they get rid of your lead following you? I really enjoyed that in HG/SS. It just doesn't make any sense to me.

You know GameFreak! Two steps forward, one step back!

I do hope it's back in the third version. It's especially baffling seeing how they'd only need to make walking sprites for the new Pokemon. Most of the work is already done!
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My feelings on these games are very positive. I didn't get into Pokemon until a few years ago, and I'd only played part of Yellow, and all of Diamond and Soul Silver. There are so many little things I could list that are huge (and often overdue) improvements, like assigning multiple items to Y, de-emphasizing HMs, and the list goes on. There are definitely poor design decisions as well, like removing walking Pokemon, 'Deposit' and 'Withdraw' still existing in the PC, etc., but overall I think this was a big step in the right direction.
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Also, I'd like to mention, I have all the starters from every gen in my White now, as well as Zorua and Zoroark. I can breed any of those if anyone wants them.
And
a couple protips!Have you seen how much experience Audinos drop? You can force them to spawn for easy leveling. Just run back and forth (not over too large a space) beside any grass. After 200 steps-ish, shaking grass will appear, which more frequently has Audinos in it than not. Make sure you listen for the noise in case it spawns behind a tree or something.
And if you want to activate the Zorua/Zoroark events with the Shiny Beasts and Celebi, do NOT transfer them through the normal Poketransfer Lab. You have to talk to this guy in Castelia and give him this passcode:
EVERYONE HAPPY
SIMPLE CONNECTION
which activates the Relocator on the opening menu and then you transfer them through that.