The entire hiring process consisted of three phases.
The first phase is an online multiple choice test covering basic programming skills and questions on analytical thinking (of the type you'll normally see in a GRE or GMAT test). There were about 30-35 questions and I was given a maximum of 3 minutes for each question.
The second phase is a phone interview. They questioned me in detail about my resume, all my projects, and asked me to choose one from the different projects listed in my resume. They then went into quite some detail about the project, asking me to describe what I did, the major challenges, how I planned the development, and how I tested the code. After that were some basic technical questions. They will definitely ask you which programming languages among the ones listed on your resume you are most comfortable with and quiz you in detail about it. Since this round is on the phone, they normally will not ask you to write any code, nor will they give you any code. Apart from programming language concepts for one or two languages, there will be some questions on sorting and searching algorithms and data structures, like hash tables, BSTs and their complexities, their advantages, disadvantages etc.
The final phase consists of two or three in-house interviews.
There will be a round of HR interview which is usually 1:1. Be aware that I was asked in very minute details about everything on my resume. I did expect to be quizzed about these things, but not in such minute details. There are the usual HR questions like why do you want to join Bloomberg, where do you see yourself in 5 years, why should we hire you (asked in a very curt manner to really catch you off guard) etc. so be well prepared for those.
Then comes a technical interview round, which is usually conducted by two of their engineers. They will ask you which is the language or languages you are most proficient with, and then quiz you on that. Be aware that you should only say you are proficient in a certain language if you really are proficient in that. There are no bonus points for claiming to know more languages and then not being able to prove your proficiency, and if you can't you will most likely not be hired. The logic is that they want to know how good you really are in things you claim to be really good at. They will usually ask you to write code for two or three problems. They may start with a simple coding question, before moving on the more complicated programs (usually involving recursion or use of a data structure). The emphasis is on being able to write clean and efficient code, along with the use of an efficient algorithm for solving the problem. They will definitely ask you the reasoning behind writing the code (sometimes line by line). There is also emphasis on low level concepts (like how the stack, heap, data segment works, what's stored in there, how the Stack Pointer behaves in different situations etc). Along with writing code, they may write down some code snippets, and ask you if it will compile, if there are any errors, what those errors are, why they come out etc. My preferred languages were C and C++ so they asked me some seemingly odd code snippets to test my understanding of the mechanisms involved in inheritance, polymorphism, templates, operator overloading. There may also be a few questions on the STL. Also related to both containers and memory management will be questions about the ownership of pointers or objects placed in containers, what delete and new do etc. There will be questions related to algorithms and data structures as well. These could either be by themselves or they could be as a part of a programming problem. Be sure about the complexities of all the basic sorting and searching algorithms and data struct operations too since these may be useful is such situations. Finally, they will ask a few puzzles (usually just one or two) to test your problem solving capability. The entire interview will last about 1-1.5 hours (depending on how well you're doing). Most likely, the interviewers are going be really skeptical about your answers (regardless of whether you're screwing up or you're near perfect) - they want to know how confident you are about your answers. Don't panic, this is normal. Just be sure of what you're doing, and cross check your code before you tell them that it’s final.
If you manage to survive through this technical round there will be an interview conducted by a Sr. Manager. This one is comparatively low stress. Not too technical. Mostly they want to know how well you fit into the team, where you will fit in, your attitude etc. I would suggest that you talk about things like how you planned your projects, how you worked in a team during your project work etc. He/she may also ask you a puzzle/brain teaser, but I wasn't asked any. You are encouraged to ask questions about the position, the company, the work culture, the management etc.