According to WinRumors.com, Microsoft will push out a security update for its Windows Phone 7 devices, possibly as early as May 3rd. It will ensure that mobile devices are not adversely affected when trying to access websites for which digital certificates were recently revoked by certification authority Comodo.
It is unclear at this time how Microsoft will distribute the update. It is possible that it could use its OTA update system rather than rely on its carrier partners.
No other functionality is slated for what now appears to be the third Windows Phone update to be issued by Microsoft.