Tufts Immunology invite- half day information session/interview on February 24.
I e-mailed them early last week since I was getting anxious, and got the same generic "all applicants will be notified at the end of May" response. I guess they tried to send me an invite the day after I asked about the interview dates, but they mistyped my e-mail address, so I didn't get it until they realized their mistake 5 days later and sent it again. It looks like they may be a little slow with getting invites out, but looks like they're coming, for all those who are waiting!