I can't say I was too crazy about it at first. There's this trend toward "Pale and minimal" I see everywhere. The changes here for example mirror changes I have seen in say an itune player, gmail, facebook.
Things I dislike: The quotes don't have distinct boundaries. It feels too formless and washy. I need old fashioned boundary markers - the clearer the better.
Alternate idea: Use the quoted members icon in the reply with a cartoon speech bubble coming from it. It's clear, direct and to the point and has some entertainment value.
Other thing: The pale effect. Way back in the beginning the blues were fairly deep and the boundaries and borders seemed richer. The 2nd revision paled that out and this latest one pales things out even more. It made me feel like I was getting something watered down, cheaper, less good. It also made it difficult to read in general and though I don't use my phone for internet I have seen how it looks and the effect is even worse.
Alternate idea: Customizable skins but I realize that may be very impractical or even impossible.
It is a general problem all over the web. Facebook and Gmail make these changes on a regular basis and it drives most everybody including myself temporarily crazy until our eyes adjust. It's like going out to your car one day and suddenly finding the gas and brake pedals are now reversed, the windshield wiper lever blows the horn, the headlight button turns on the stereo etc . . . .
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X 10 on a bad day. I'm just curious of the reasons for the change. Public demand or is new layout cheaper to maintain?
All that said I'm starting to get used to it. The search functions have been buggy from time to time but I assume those will be ironed out eventually.