I updated to OS X 10.10 after a day it was released – only to be stunned by the really, really ugly looking UI. @francispereira dubs this new update as “Polio infected”. There’s transparency where it should never have been in the first place, and the font smoothing engine is gone haywire with the new system default font, Helvetica.
Let’s fix it:
Drop the transparency
Open System Preferences(type sys in Spotlight). Open the Accessibility settings(second last row, extreme right). Check the checkbox that says “Reduce transparency”.
Revert the system default font to Lucida Grande(the font used in OS X 10.9 and earlier)
Download this app which I found here. Uncompress the downloaded file, then right click on the extracted app, and click on Open. Then click on the Patch and Install button in the dialog box that appears. It will then prompt you for your system password, as it copies Lucida Grande from /System/Library/Fonts to /Library/Fonts, and then patches it to be the system default font.
Next, log out and log back in to see a more usable Mac.
Seriously Tim, you ought to check yourself before you wreck yourself.