BIS v2.5 will bring HTML email
This article contains unofficial information.
RIM appears poised to launch the latest version of their Blackberry Internet Service on June 28th. Most notably, this v2.5 upgrade will finally bring native support for HTML email in preparation for the upcoming 9xxx family of devices, such as the Bold and Thunder. Other improvements should include OTA upgrades and some calendar enhancements. Changes may not be backwards compatible with older devices however, so to finally get HTML email you may still be forced to upgrade your Blackberry.