SLevy2015:
It depends on what you are trying to optimize.
If the new job is to increase your pay and gain managerial experience, then you should take it. Right now, you have no b-school acceptance in hand so you might have to assume you are not getting one this year. It looks like it's going to be another very competitive year and while you smartly applied to other schools for R2, nothing is a guarantee.
If the job is to increase your chances of getting in as a reapplicant, then it might be slightly more difficult because it complicates the story. Side note: there are no prerequisites for banking so you don't have to worry about recruiting for that role if you do get into school and decide to pursue that path.
As for your current company, that's a tough situation now that the cat's out of the bag. My best advice is to try to be as upfront as possible at this point. Since they know you're on the move, you might as well work with them to smooth things over and promise a good transition. They may be grateful to have the support and advanced notice of your eventual departure so they can plan accordingly. I'm not sure you're going to be able to delay this other offer to figure out the results of R2, so you might have to keep recruiting on the side just to hedge.
Fingers crossed that it all works out as you wish,
Admissionado