Google introduced new logo on 1st September. just after a month unveil the new structure to Google, they updated the logo too. The logo is still a word mark, but now its in San-serif font style, it looks modern and soft. The logo is without any shade, that look more softer than before. The logo is bit resemblance with new subsidiary company called Alphabet. Alphabet logo is new unadorned look and the Google logo also followed the Alphabet.
The Technology company Google overhaul the structure into a Alphabet, with Larry Page as CEO and Serge Bin as President of Alphabet Inc. while Sundar Pichai as the new CEO of Google.
Google mentioned their history of the logo changes in the Google search engine itself, take a look on
--- Google Logo History
And the video also introduces the logo history. In that they mentioning past 1998 to 2015. Google also changed their tiny 'g' into Capital 'G', it is combined of all four colors of Google. Now they put it on the home page logo as animated type. First the previous logo shows then one pencil sketched hand come and erase the logo and the same come again with color pencil and draw a new look logo in San-serif font format.
Benefit to Google is to making a simple and good looking logo is major consideration to small screens. The San-serif simple font small size get easier to read and for lower bandwidth connection can quick to load with the 305 byte logo by comparing the previous 14000 byte logo.