In 2006, there there was no need to put the GCSE and A-level grades down on the Oxbridge application form.
Is this still true now in 2009? I have been offered a place at a top music college in london with an offer of 2 Es. I'm thinking of dropping 2 of my current A-level subjects to leave me with more time to do music. (I'm currently doing 4 and struggling to cope with everything plus all the music I do). Is it wise? If I get a first in the Undergraduate course, A-level results wouldn't matter then?
To address your questions:
1) I went to a small liberal arts college in the U.S.
2) I did not apply for undergraduate study at, in my case, Oxford.
3) Whether or not it's expensive probably depends on how you define expensive. It is a bargain compared to the U.S., at least for UK/EU applicants.
4) A masters/doctoral degree obviously is higher than any undergrad degree. It might be harder to get in for undergrad as most competitive applicants will apply after A-Levels, IBs, etc. Not as many people apply for postgraduate degrees, especially in the purely academic fields. That said, the entry requirements for postgraduate applicants are still very high. This is my long way of saying that I don't think it is any less prestigious getting a postgraduate degree as opposed to an undergraduate degree, it is just less common. Plus, I am of the impression that the postgrad community is much more international than the undergrad community, which primarily is British.
What about American universities such as Harvard and Yale?
With regards to postgrads being easier to get into, the only reason there's less applications for postgraduate study in Oxbridge is because a)less people want to do masters and phds than batchelors and b) you need a top class degree and far less people have top class degrees than good A levels.