I do think it's a little odd there is no notice of any deadlines in the acceptance mail. Just that "in due course" we will get a letter and in two weeks we'll get intranet access. I for instance have to choose between Cambridge and Oxford and the deadline for Cambridge is in the end of the month. However, it'd be nice to have both mailed acceptance letters with further info on fees, deadlines, and possible scholarships, before choosing...
It is also interesting that Cambridge does not offer a bursary until you've reserved a seat - and it is by no means granted that you get one. The bursary request is part of the financial form. Also, the Gates Cambridge Trust applications are still rolling. Basically, one must first choose to pay a deposit and then hope for a scholarship, whereas most American schools meet the candidate with an offer of admittance and a scholarship simultaneously.