Elder Scrolls IV: Oblivion Q&A

IGN PC has published a two-page Q&A with Bethesda Softworks' Gavin Carter, quizzing the producer about guilds, the Radiant A.I. system, and the differences between the PC and Xbox 360 versions of Elder Scrolls IV: Oblivion. A snippet:
Q: What are some of the new abilities you'll gain when you max out your skills? For instance, what happens at the highest level of mercantile, heavy armor, alchemy, axes, security, acrobatics, marksman, etc.?

A: Every skill has a system of four perks that unlock when you raise in skill level. From zero to 25 you're ranked as a Novice, and at intervals of 25 from there, you rise in rank to apprentice, journeyman, expert, and master. The perk features themselves run the gamut. The magic skill perks open up access to higher level spells, while perks for a skill like athletics allow you to regain fatigue levels faster while running. Other skill perks open up new abilities. A master of block can do an automatic counter-move after a successful block that disarms an opponent. A master of armorer not only can repair magic weapons and repair weapons up to 125% condition, but his or her repair hammers never get used up.