Pros
Capital One is a huge company so I'm really only reviewing the Global Finance organization, where I had the misfortune of working for four years. For the right person, it can be a great opportunity. It's a big, well-run company and it doesn't expect you to work more than 40-50 hours per week (granted, strenuous hours in a Finance role). If you work in Richmond, the West Creek facilities are fantastic. I saw plenty of not terribly talented people in the their late 20's making (low) six figures without really knowing all that much or working that hard. Especially in the undergrad program (FRP) the kids are treated really well with tons of training and networking opportunities.
Kontras
Capital One has a brutal performance management system and they really do fire people, even good people, and lots of them. In the area I worked, pretty much anyone over the age of 40 was toast if they weren't a Senior Director or above. The Senior Manager and Director levels ( for those age 40+) were constantly targeted in re-orgs and downsizings. And it's not like you get great experience in Capital One Finance. What you learn there is very internally focused and not valued outside of the company. The people I saw getting caught up in re-orgs were not finding comparable jobs in other organizations. For anyone over the age of 30, joining Capital One Global Finance is a horrible career move.