First had a quick 30 min phone interview- describe Bloomberg, the role you are applying for, good/bad customer service, generally why you're interested and would be good at sales, and know 1 thing that is going on in the markets today (you guide this- so even if you don't know the markets, just know one topic really well and have an opinion on where you think it is going and why)
Second/Final Interview was the same day for me- I was interviewing with 3 other candidates, we each sat at a Terminal with a current analyst for about 30 min- pretty casual and I could ask him some questions, then shadowed and went on a tour around the building with another analyst- again was pretty casual and just was able to ask a lot of questions. Then went to a 2-1 interview with a financial and sales rep for about an hour- they asked me to go through my resume, why Bloomberg, good/bad customer service, important qualities of a good sales person,again- 1 thing you're following in the markets, and I was asked some teamwork stuff- like a time when you had a conflict and overcame it, nothing was too unexpected or out of the ordinary, have some questions to ask them at the end, then did a group activity. Afterward, I was called back and they let the other candidates go- I don't think this means they won't be called up later to have a skype interview (or in person if you're in NYC) but it is a good sign if they want you to keep interviewing that day. I had 2 interviews (both with senior members) - asked me similar questions about my background, interests, why Bloomberg.
I wasn't asked any technical questions (about bonds vs stocks, ETFs, etc) but I probably would be prepared for something like that since I think others were asked those questions.
In all- I would be prepped for any classic sales questions (what are the qualities of a good sales person, sell me something, etc), know why you want to work for Bloomberg (this is important for them), 1 story about the markets, and some basic finance terms (investopedia or wall street oasis guide is great if you don't have a background in finance)
Hope this is helpful. I am waiting to hear back. I don't know yet on the timing between second/final round and when they make their decision, but it was a quick turn around between the first phone call screen and the invite to come into the office. They also email you if they don't want you back for phone and in-person rounds so you'll know if it is a yes or no.