BuddyPress.org

WP upgrades, especially security and maintenance releases (ie when the version number is 3.x.x rather than 3.x), are generally very unlikely to break any plugins, including BP. I’d recommend that you upgrade to maintenance releases immediately.

Feature releases, like WP 3.0 and 3.1, are somewhat more likely to cause problems with plugins like BP. But the BP core team works closely with the WP core team to ensure that BuddyPress is ready for whatever changes come along ahead of time. If there is something in BuddyPress that absolutely cannot be fixed prior to a major WP release, we’ll do our best to warn you about it before you upgrade.