Phone screen with HR rep, then a block of 4 hours to meet 6 people. One person did not show up at the appointed time to meet with me. A final face to face interview was requested and despite me following up, no time was every set. After several follow ups,I finally received a rote rejection. A block interview format is great - but do make sure everyone who is expected to meet with the candidate shows up. Also when you send a request for an interview at 9 PM at night on a weekend, it does raise questions about work-life balance.
And do communicate with your candidates. I shouldn't have to beg for a resolution.