The Graun today is reporting that Gove is considering introducing (or going back to ) numbers rather than letters to denote GCSE attainment, with possibley a greater degree of differentiation within previous grade bands. www.guardian.co.uk/politics/2013/may/15/michael-gove-scrap-gcse-plan
As always, nothing is new under the sun, for a period in the 70s and maybe earlier O levels were given numbers rather than grades and there were two numbers for each letter (ie 1 and 2 became A, 3 and 4 B etc).
That having said, for once I'm not automatically massively opposed to Gove's suggestion - if he is changing the goal posts so dramatically but not changing the exam name, then it seems sensible to have a completely different scoring scheme - so that it's obvious in the future that the exams were treated differently.