Maybe it's just a screenshot artifact, but did you change the calming LW green to a more blueish, unpleasant hue? If so, let me be the first to say They Changed It, Now It Sucks.
(No, I don't have anything more substantial to comment on.)
The colors look the same to me. The first letters of the words are capitalized in the new headers, though, which means that the first L shows more of the darker, bluer green than the old header's L did. That might be what you're noticing.
Design sketches
1. Notes on differences between these images and what we're planning on implementing:
2. Meetup widget in sidebar, listing the 5 nearest meetups occurring in the next 2 weeks, linking to:
(something like right-click & "Open Image in new tab" will help here)
3. New headers: