Google Webmaster Tools has a Diagnostic section dedicated to Mobile Crawl Errors. Someone over at WebmasterWorld recently noticed a new warning that reported that two pages of his Non-mobile Web site were “too big for common mobile devices, with the error message “Document size too large”. ”
This feature seems very new, since it’s not documented unlike other features found in Google Webmaster Tools.
The author of the forum thread believes that the size threshold is somewhere between 21kB and 30.3kB.
Note that currently, the W3C recommends in its Mobile Web Best Practices that site owners keep their pages under 20kB so that anyone using a mobile browser can view them.
I hope Google will soon confirm us what is the size limit for a page to be accepted in its mobile web index, and if size has an influence on rankings…