Star Alliance is probably the best airline partnership out there. United, US Airways, and Air Canada in North America. BMI, Lufthansa, and Swiss among others in Europe. Asiana, ANA, Singapore, Air China and a couple others in Asia, which is probably the strongest aspect of the alliance. The Star Alliance Gold status is the highest status within Star Alliance, with benefits such as lounge access for any of the Star Alliance partners on any international flight, priority check-in and boarding, and extra baggage allowance.
Now you can get Star Alliance Gold by becoming Premier Executive on United or Gold on US Airways, but that requires you to bank 50,000 actual flown miles or 60 segments in one calendar year. There’s actually a better alternative: bank miles with Asiana Airlines when flying with United, US Airways, or any other Star Alliance partner.
Asiana Airlines requires you to fly only 40,000 miles or 50 segments and the qualification period is 2 years, not 1 year, to become Asiana Diamond, which gets you Star Alliance Gold. Not only that, your Asiana Diamond status is valid for 3 years, not just 1 year like United or US Airways.
No more banking miles with crappy US domestic carriers.