Just got approved for this card, yay! Here are a few details, let me know if I'm leaving out things you would have liked to know.
- Info at the time of application:
- 3 months ago: New card and hard inquiry (Experian)
- 12 months ago: New card and hard inquiry (TransUnion)
- 18 months ago: New card and hard inquiry (TransUnion)
- 10 years ago: New card
- 4 credit cards open, none closed. Never had any other loans.
- Credit utilization was probably beteen 1% and 4%, out of 50k credit. Not exactly sure about timing.
- (I mention utilization because I heard that Capital One likes people who carry a balance, not sure whether that's true.)
- Instant approval
- 7.5k credit limit
- I just got it, so I haven't tried to use it and I haven't gotten it in the mail yet. So there could be more drama to come.
- To get this card, you have to either be in a union or a member of Working America. Some of the fine print in the application said that you or a family member have to be in a union (didn't mention Working America). I was asked to pick which union I was a member of, and selected "Working America" from the dropdown. (Working America is basically an email list and discount program. See above for discussion about that.) I didn't have to give proof at signup.
- I did not have to provide any documents of any kind.
- I had all my bureaus unfrozen.
- I probably got the triple pull, not sure yet. Experian was pulled for sure.
- I used the preapproval tool and it said I was preapproved for the two "better" cards out of the three (didn't say anything about the worst one). I applied for the 1.5% cash back one.
Update: I did indeed get the triple pull.
Another thing I forgot to mention: Now (I think this is a new thing), when I go to check my eligibility for the AT&T discount (my way of trying to verify my Working America membership), they send me an email with a lil membership card and a member number. I didn't need to provide that to apply for the card but I'm holding onto it in case they get on my case.
Moved this thread into credit cards forum.
Feel free to create a new thread to continue discussion on approval. 
Haha, that is also what I'm wondering! I'll let you know, hopefully I never find out. Would love to hear others' experiences.