Social document sharing service Scribd has made a major announcement today: they’re in the process of switching millions of old Flash-based embeds scattered around the web over to the new HTML5 layout they started implementing last year. The conversion process will be automatic, shouldn’t break anything for publishers and website owners and, most of all, will dramatically increase the quality and speed of Scribd embeds.

As Scribd swaps Flash with HTML5 on old document embeds, iOS devices like the iPhone and iPad will benefit from the change: the HTML5 tool developed by Scribd is fully compatible with iOS’ Mobile Safari and now every webpage containing a new or old Scribd document will be perfectly viewable on Apple’s phones and tablets.

When Scribd launched its HTML5 reading platform last summer, they said user engagement with the Scribd experience “surged”. The conversion of 20 million embeds to HTML5 should definitely make things even better for Scribd.