I applied through my university, and a recruiter then reached out to me requesting to complete a HireVue challenge. It was a mix of behavioral questions, like "Why IBM?" and basic coding challenges. Email said to allot 3 hours, but it only took about 1.5.
After I passed the coding challenge, I had two video screens - one to talk about job fit (GUIDE) and one to assess coding competency (GURU). The Guide interview was more of a conversation and an IBMer giving me the opportunity to ask any questions that I had. The Guru interview was only one coding question and not terribly difficult.
After these were completed, I was invited to a Finish Line event in Boston, MA. It was apparently the first of the year, and the first time they were trying with a new format. The event lasted about 48 hours, and was designed to tell you about who IBM is and to sell you on the idea of what they are building via panels, talks, and a Finish Line challenge, which is completed in a team of 6. From the Finish Line event, it became very clear to me that IBM values their greatest asset - people, and spared no expense even for job candidates. From what I understand, almost everybody who went to the event received an offer.