For a single commerce major, would accounting be the safest in this climate? I'll be graduating in 2013 though.
It really all depends. If you are intent on heading into accounting and sure of this, then I don't necessarily see anything wrong with doing a B.Com(Acc). What other areas might you be looking at?
It depends on where you apply to, what the culture of the company is, your extra currics, work experience, confidence, communication skills etc. For a lot of companies, the degree you complete is far from the crucial factor, even in this climate. I got to the final stage with Westpac's Business Banking and I met a guy there that was doing a Philosophy/Arts degree.
Obviously, if you broaden your options by doing a double degree you have more opportunities when it comes to grad, but if you are intent on following a certain path I don't see you would be improving your chances massively by studying extra fields.
That said, i'm doing a Acc/Fin double major but this decision was made as much through interest as it was because of job opportunities.