If you are interested on flying your domestic for free for at least one full year, you should take a peek at my post here.
Now the 50k offer is back, but you have to spend $2000 within 3 months, I remember last year or earlier this year, there was no spending limit at all, however, it increased to $1000,$2000. The trend for credit card bonus points/miles is, you still have a lot of those cards in the market, the spending requirement became more and more challenge.
MMS has published the detail of this news, have a look……
If you search my blog, you will find that I have a lot of ink on "Southwest", for example, I only redeem two people miles for the family of four, thanks for the Companion Pass. This coming Dec, our family will fly to Orlando with only paying $5 per person for the tax of our flights.