The Google+ effect is spread across the board with Gmail. The new login page for Gmail will also start complying with new design, Google is introducing across all its products and services.
So do not be surprised if you come across this login screen for Gmail in the near future.
The difference is with the nice bold button asking visitors to create an account. It also shows links to their Blog, Twitter, Facebook and Buzz profiles.
The new design seems to conform with Google new unified design theory and brings in more uniformity across its products.
If you go the current login page for Gmail, you will see a link at the bottom which will load the new design as preview.
Do look it up and let me know your views through your comments.
Link: New Gmail Preview