Guys, it's not the end of the world, you didn't have your wang cut off or something this afternoon. It's just a HBS application interview.
I applied to R2 at HBS and didn't get an invite today (M, Canada, 23, 690 GMAT, 3.9 GPA, 3 Years WE in Marketing Communications), but it's no reason to cry! I still have McGill, Concordia, UofT, Notre Dame, and York to focus on. Plus, you never know what could happen. They did say 50 are still to go out. They could have also had a technical glitch with your particular email.
Honestly, I feel sometimes like reading posts on here is the most intimidating thing about the application process! I feel like I'm not engaged enough or something since I only got 690 on the GMAT and have only applied to six schools! I think some of us get too wrapped up in comparison and think because 5 or so people on here have told us they got interviews, it makes us feel stupid because we didn't. Who cares? Harvard's got a strong brand, but so do a lot of other schools.
Good luck to everyone, but nothing's set in stone yet... you never know, a bunch of people who can't type their name right might apply in R3 and you'll get an interview then. Perhaps everyone who gets an interview sucks and they invite you April5 for a phone interview. No point giving up hope, but there's also no point in giving up your positive attitude either.
Good luck to us all who have applied to Harvard around the world, and good luck to us getting in there or wherever our lives take us.