When you submit a link that has been previously submitted it upvotes the previous submission. It's most likely that a large number of HN users all tried to submit the Techcrunch story at the same time, whereas the only way this submission gets upvotes is through people clicking, reading the story and then upvoting.
TechCrunch story is a bit juicier and easier to digest. Maybe that's the reason, no idea.
That article also mentions the rumor that Braintree has been in stalled talks with Square. That's an interesting rumor but unfortunately attributed to unprofessional "we heard from sources" source.
This one was posted 6 minutes before the other, after all.