I honestly don't see it calming down any time soon. In the past year, applications have risen steadily by 3-4% each year since about 2002 (I'll try and find the census data from UCAS I was looking at). Apparently, this year, applications increased 30%.
I put a lot of that down to the tuition fee scare and the fact that people don't want to defer, but think about it like this - that isn't going to go away. People go into Medicine for different reasons, whether it's because the enjoy the idea of helping people, the idea of a very intensive and applied scientific course/job, or, in reality, job security.
I think a lot more people will be applying for Medicine on the sole grounds that it leads to a secure job position that doesn't really fluctuate that much, no matter the current world affairs. Those people would have been on the fence beforehand, but they will now be convinced that Medicine is for them on the advice of their parents and peers, even if they know it isn't.
So, I would definitely go for another gap year. If you have the grades, and you have the ECs(where relevant), the work experience and the determination, you stand a much higher chance of getting in after a gap year than you do through GEM. GEM is going to be showing the same trends, and it's competitive enough already. More and more science graduates will opt into doing Medicine than the alternative of a job that no longer exists.
That was a bit of a depressing post, but it's my honest appraisal.
EDIT: I may have put a bit too much emphasis on the whole 'job security' thing, but despite what people say, I do think that can be a factor, especially in graduates.