First, I started playing OOTP with 2006. I did play 5 while waiting for 2006 to be released.
I have to say that I find most of the complaints about the interface are silly resistance to change, but there are some valid criticisms.
1) Clicking and click&drag are not "crisp" enough. This is frustrating and should not be an issue.
2) The html pages are necessary and must remain. We online leaguers use them to avoid work.
However, I see no reason that the html player sheets ever need to come up in the game. They just need to be available.
3) Wanting to see your lineup's batting stats (as in 2006) and wanting depth chart to be integrated into the lineup screen are not mutually exclusive desires. It's silly what we need to go through to see stats and set our lineups. I'm surprised that this didn't jump out at everyone involved with 2007. At the very least there should be a filter for starting lineup, but really there needs to be a toggle to move back and forth between depth chart and batting stats.
4) There are a lot of little things that would make the interface more polished.
Wanting to abandon the interface all together to go back to 6.5 is ridiculous, though. Saying you don't use bookmarks (even temporary ones) is like saying you've decided to make it harder to play the game. And 2007 really is much better than 2006- I play in two leagues, one 2006 and one 2007 and I now dread loading up 2006.