One of the most entertaining parts is the Prescreen and Opt Out Notice, which is compliant with 16 CFR part 642 and looks like this:
The actual notice it refers to looks like this:
The important thing to remember is that "pre-approval" is an etymological weapon of confusion: it does not mean "all you have to do is say yes and you will get this exciting new credit card"; it actually means "say yes and we'll then really check your credit and might even reject your application, because we didn't really check carefully the first time." The consequence of a rejected application -- thanks to the Rube Goldberg-ian algorithms in place for this "Get punished without doing anything" setup can be a dark spot on your credit. Opt out or just hurl this thing into the shredder.
Read the finer print at the end of this exciting letter to learn about MCCs (Merchant Category Codes), which offer these credit companies another weapon to deny you "rewards"; take a look at the big fat disclaimer at the end:
That travel agency is most likely Travel Leaders Group, LCC, which spun off from Carlson Travel Group in 2008.