It's a little scary to think that the decisions we make during ages 18-22 can have such a huge impact on the rest of our lives, but it looks like it does to a large extent.
First, America is more meritocratic than ever before. Top finance jobs which back in the 60's were only open to rich east coast WASPs are now availabe to those who are qualified, regardless of their ethnic backgrounds. Second, firms are increasingly using undergrad name brand and gpa as initial screens before deciding who to interview in the first place. At a lot of banks and consulting firms, they even ask for your SAT I and SAT II writing scores (mckinsey does this for a fact). Furthermore, the first job out of college often sets you up for future opportunities down the road.