Update: The Nihilum Wiki is currently password-protected, but the mastery information is available here.
The Nihilum Wiki has been making some great discoveries in the Cataclysm alpha client files, including new UI elements, factions, and titles, but here's some of what we know you really like: math. They've broken down how each talent point you spend in a tree will bolster your spec's three mastery bonuses.
Brief summary for those who haven't been following: each talent point you spend in your "main" tree will give you three separate bonuses that benefit your class, scaling up as you get more points. The first two are basic bonuses like spell power or melee haste, while the third is one specific to your class, such as a chance for your healing spells to splash to nearby targets.
Formulas after the break.