Standard process like everyone else described - initial application, 2 hr analytics test, call with HR, call with Ops Manager and then 4 hour interview with various managers who asked Uber centred questions. The interview times on the actual day were messed up, but I didn't mind as I know this stuff happens. Generally I felt the process was ok, a bit arduous considering the level and role.
My real negative point was with HR. The day after my 4 hour interview I was sent a generic two line email saying I didn't get the job. I felt this was lazy and rude given I had invested 12+ hours of my time in their process. I then emailed to ask for feedback and was given the opportunity to schedule a call with the HR rep.
Fast forward to the call and the HR rep gives me a one line generic answer as to why I didn't get the job. When I pressed for more specific feedback (remembering they had recorded 4 hours of interview material), I was told that's all they had. I then asked for a copy of my interview notes, which in the UK is by law supposed to be made available to candidates under the Data Protection Act, I was told Uber don't give it out. After a bit more back and forth with the recruiter explaining politely my motivation behind wanting my interview notes, all I received was a rude tone and not even a goodbye.
I'm actually stunned that a company like Uber who claim to embody "start-up" culture and great user experience could have such a corporate (or worse than) approach to hiring. I don't know if the issue is with HR, as I've seen other similar experiences on Glassdoor, or if a quick-hire, low-expense approach is being bred due to fast growth. Anyway, I'm really disappointed in Uber and whilst I like the company in general, I wouldn't recommend going through the process if you have alternatives - it is very time consuming, and you're treated like a disposable if they decide they don't want you.
I'd also encourage those that do, to challenge the interview feedback and ask for your interview notes if you live in a country where it is offered by law.