Someone posted how with the memo, category, and tag fields all being on the second line of the 2 line transaction, real estate was getting a little tight. But with the new tabs at the top of the screen (to jump from HOME to CASH FLOW to INVESTING etc.), it does make navigation easier from account to account enough so that for the first time, I haven't felt the need to keep the account list opened on the screen all the time. Ergo, using the full width for the register now is really cool (I know you could do this before, but the new nav tabs make it more palatable).
Having a drop list of 'tags' and categories is nice to have when assigning same. With the method of categorizing the categories, it makes it easier to assign one via point and click as well. This might have been available previous to Q2008 and I just noticed it for the first time when playing with the register.
Just mentioning some of these things since I don't want to come across as a nay-sayer for Q2008 - they've done some nice things to it as well.