A majority of the changes are not be visible; these tweaks go along with recent updates that were made to Stack Overflow:
- We have updated the site's CSS to a newly refactored LESS system, so that it's easier for us to fix SE network CSS bugs globally and launch new features in the future.
- We've updated most of the graphics to SVG for retina support.
- We have fixed a LOT of obscure bugs that arose when new features were not thoroughly tested across the entire network.
- We've launched the new user profile.
Visually it should "feel" the same as the old site with slight layout adjustments.
This update should retro-actively fix most of the old design bugs. If you see any new bugs, or old ones not yet fixed, please post an answer here to let us know!