Google+ Widgets team has released an all new redesigned +1 and share buttons that look consistent with Google+ badges.
Another reason behind this change is to scale them across many different screen resolutions without losing quality. For that reason they switched all their buttons to use SVG to render the iconography and Roboto font for text according to Paul Lindner of Google+ team.
+1 and share buttons after change
There’s even some SMIL(Synchronized Multimedia Integration Language) animations hiding in there too. All of this is perfect for your new high dpi laptop, tablet or phone.
NOTE: If you are already using +1 or share buttons you don’t have to do anything. These changes are automatically applied from the server-side.
Tryout on various devices and please share your experience.