Macbook Pro Processor???

What is your current 13" MBP not doing for you that you need it to?

Each program running at a moment in time takes up RAM. The CPU or central processing unit, does the majority of processing that 'matters to users' besides the graphics card, meaning - it runs your programs. Run too many programs, or programs that need too much RAM for data, and instead of storing that data in fast memory, it will start to use hard drive disk space to 'swap' out memory to temporarily, making a system slow dow, usually significantly.

The faster the CPU, the faster a pure processing load (meaning not sitting waiting for user inputs) of the same size will be completed. The faster the CPU, or the more cores it has, the more work it can do seemingly or in reality, at the same time. The more programs can run reasonably well at the same time, or one or a few programs very quickly, etc.

That's about as simplified as I can get, I think.

The real difference between the base 15" and the 2.2GHz onwards is the discrete graphics card being faster in the higher models, and going from 256MB of video RAM dedicated to the graphics card, going up to 1GB of dedicated video RAM. For casual non-gaming use, I wouldn't expect a huge difference between CPU, GPU or RAM. I wouldn't expect much noticeable difference doing normal photo touchups and typical home movie type editing, either, or not to the point of "needing" the 2.2 or 2.3GHz and upgraded video card. Any of them will be significantly faster than your 13" in both CPU and graphics (regardless of what year your current 13" is..)

Why not pick up a refurbished or used model instead? And - what is your 13" MBP not doing for you that you want a new one to?

 

Dont upgrade to the 15". Not worth it.

Dont forget, upgrading to the 15" gives you a better GPU.

 

Buy one because you need one not because you want one. But if you REALLY want one, go for it.
Talking about the 15", I'd say go for the 2.2Ghz so you'd get the better GPU.

 

The base model will work fine. I'd suggest upgrading to 8GB memory after you get it as well, as that can greatly improve PS performance