I received an offer for Silver or Gold Elite membership.
To qualify I have to make 2 roundtrips for Silver and 5 roundtrips for gold by February 6, 2006. I will also get 10,000 bonus miles for 2 trips which will top off my current account. The level attained would be good through February 6, 2007.

I want to know if these levels would be worth attaining so I could get upgrades in the future. I'm not sure how much I can use it, but I am planning a trip from PDX to San Juan PR next year and thought an upgrade could be nice.

If anyone has any advice on suggestions for a route to take, I would appreciate it. I have found ORD (which is where I'll start) to Detroit is about $120.
Thanks for any advice!