I shot my resume into Palantir's job portal on a Thursday night and heard back from a recruiter <24 hours later. I was quite impressed by how it's not a black hole.
Schedule was as follows; I always heard back for the next steps within one week.
Recruiter phone screen: Wednesday
1st phone interview request: Thursday
Phone interview with PQE: Wednesday
2nd phone interview request: Tuesday
Phone interview with PQE: Friday
Invitation for on-site interview: Monday
On-site interview: Friday
Phone call from recruiter with no offer: Wednesday
The on-site interview consisted of a brief check-in with the recruiter, three 1:1 45-minute interviews with PQEs in the morning, lunch and office tour with two PQEs, then a product demo (which started late that day due to technical difficulties, so the other candidates and I were left waiting in the lobby for maybe 20 minutes). I was pulled out of the demo early to interview with a fourth PQE. After this, the recruiter came, gave me a T-shirt, and told me she would call me next week with an update. In total, I was on-site from 10am - 4pm.
No luck this time in getting a job offer. I still had a positive experience interviewing, though. The recruiter was timely in her responses, the employees I met seemed happy with their work, everyone who interviewed me gave me their undivided attention. I enjoyed the office tour -- I requested to see all the dogs, and my tour guide happily obliged. :)