Hey David,
I'm a little surprised, as your numbers aren't extreme or anything... Diabetic, yes, but not startlingly so. No idea what they'll come up with next, don't think anyone here can say for sure. For me it was gliclazide, but that was because I responded badly to metformin. There's a load of medication out there. Pills, shots...
Have to ask though, seeing as you're "not that bad" when looking at your HbA1c... Have you tried just going the low carb/high fat diet route? I think you'd be in the non-diabetic range (and off metformin) in a relatively short amount of time. Couple of months, maybe weeks? (It is a for life kind of deal though, up the carbs again and your HbA1c will rise again too).
If you're interested, check dietdoctor.com, the low carb recipies on diabetes.co.uk's site, or Dr. Jason Fung's books, especially The Diabetes Code. I think you could gain a lot just by a diet change, and you wouldn't have to worry about side effects... But it's just an idea.