As far as i know, you have to me a member of one their partners and just wait for the email.
The rewards are not great. You get fictitious money for completing surveys that take forever, and partial payment for surveys which you dont qualify for. I usually try to not qualify for them and take the stupid $.50 or so and it eventually adds up. You can redeem $25 of this fictitious money for 500 miles or $30 for 1000 priority club points.
a few yrs ago it was worth taking the quick $ as they were giving $$ and not cents
I sure do hope that they dont use anything I filled in on those surveys to decide how to proceed with their biz going forward, 90% of the stuff they ask me I have no idea what they are talking about
I just cashed in $100 for 2500 DL miles actually Im Topping off that acct LoL. It was $100 for 2000 and then DL gave an extra 500 bonus on transfers
another good thing is to get the DL Amex if you already had it no 25k bonus miles but 1st yr still free and spend what you need to top off the acct. even better as the DL amex now gives you your 1st bag free. So just use the miles up before your are charged the fee the 2nd yr