The most competitive courses are probably medicine, veterinary medicine, law, English and history and the least competitive classics, SPS, Land Economy etc (ie courses a lot of people have never even heard of). I imagine MML is somewhere in the middle, but towards the less competitive end. I only say 'less competitive' in terms of the number of applicants though. This is probably somewhat addressed by a higher number of places being allocated to more popular subjects and is the same at all universities. As others have said, you need to choose the course you feel most passionate about and are best at. That should be more important to you than getting into Cambridge, and if you apply for a 'less competitve' subject in the hope of getting in, admissions tutors will see straight through it. No subject is going to be 'easy' to get into at Cambridge; whatever you apply for, you'll still need to demonstrate high levels of enthusiasm and ability.