I am going to be traveling for 7 months around the world, I did this last time with AA, but I am looking around. I want to get my elite or chairmans level asap but also want to know who has the best perks as far as upgrades on domestic and internationl flights. Who has the best partners and also best milage desks?

any one can chime in.

United.

I am a United fan. Good routes, good partnerships. They fly the 744 which American does not.
All personal preference and dependent on where you will be going though

Agree. It really depends on where you fly, and even in some cases, like mine, what time of the day you fly. I'm sure most people would never believe that CO isn't the most convenient airline out of Houston, but, given where and when I fly, it actually is one of the least convenient. And when I found that out, I was as amazed as most people are when I tell them.

I'd suggest you look at the main routes you'll be flying and see who has the best routing and connections for what you want. Don't just look at the FF program benefits - look and see if you'll actually be able to cash in on any of them (ex. will you really be getting those comp ups?) Then, book accordingly

I fly alot of AA and United both domestic and international, AA is way better is service and upgrades/usage of SWU.

In a very general sense, I'd say UA has better partners since there are so many more of them through *A than AA has through OW, but that AA's partnerships are tighter in some respects, such as getting access to F lounges if you reach AA EXP/OW Emerald status...and this could get significantly better now that AA and BA have USG permission to cooperate more closely, which probably means reciprocal accrual and redemption on Translatlantic flights (which right now isn't possible).

OTOH, and again to generalize, AA is better than UA for upgrades. And AA's EXP desk is considerably better than UA's 1K desk.

Having said all this...

This is fine advice. So much is context-specific, hinging on your anticipated flying patterns and preferences.