Yesterday I reported at Search Engine Land based on Gary Illyes of Google's keynote at PubCon yesterday that Google is set to launch their mobile only index within a timeframe of "months." Of course, last time Gary said months, it ended up being another year but still, it is sooner and no longer just an experiment.
In September 2015, Google told us their are experimenting with a mobile only index - this was to handle the desktop only index issues with ranking signals for mobile. Yes, Google still uses desktop signals for mobile rankings and that seems like it will change big time when this mobile index launches.
I assume this means the mobile index will launch in 2017, hopefully the first quarter, but Google would not give us more information.
It seems like Google is going back to kind of the supplemental index days where they maintain two different indexes. The mobile index will be the primary index, according the what Gary said at Pubcon. The desktop index will then be turned into a secondary, more stale version.
I have so so many questions about this but Google would not answer them now. They said they will get back to us as they get closer to the launch and have a blog post about it then.
Here are some tweets from the announcement:
There are more, see SEL.
It seems, and it is way too early to say for sure, that Google will be using both desktop and mobile indexes for rankings because of how some sites strip out a ton of information on their mobile version, including links.
Forum discussion at Twitter.