pMac has posted a designer ramble in the official forums. It covers all kinds of points on character progression. Here is a snippet:
Multiple lines of progression
As earlier rambles have suggested, there are actually multiple lines of character progression within CZ (faction rank, renown, NPC contacts, combat skills and RPG skills). I wont be talking about these other kinds of progression, instead I'll focus on the classic level and skill progression system in the game. I'll talk about the other dimensions in another ramble.
OK, the core character progression system in CZ will be very familiar to anyone who has played MMOGs or similar RPG games. To advance your character you earn xp. Accumulate enough and you gain a level. This gives you skill points to spend on skills and techniques, and attribute points to spend on your attributes.
There are 5 core attributes in the game. They have a small direct impact on character performance but their main function is to limit access to techniques and implants. More on those later. In Diablo style, you spend points as you gain levels.
To read the entire post, follow this link.