You can go ahead with both of the processing. Here is my case.
I have applied for canada PR in march 2008 and also apply for H1 b visa in April 2008. At that time I dont know about new rules applied after 25th feb 2008.
I was selected in lottery and I have received my documents for H1 b from US company in december 2008. I have chosen the date for the interview in January and before the date of H1b interview, I have received the later from canadian high commision to submit my documents in 120 days. I am right now pursuing my Ph.D. degree so in H1 b interview, the consulate officer told me to fill TQQ. (Hope you know about TAL and TQQ).
I have filled that ques. and statrted to wait for visa.
Also, I hve send my documents to CHC , New delhi in april.
I have received my H1b visa in May and after 10 days received my medical, rprf and PPR for canada.I have sent all these in last week of may.
They kept my passport for 6 months and finally I have received my visa in november.
So, apply for both if you want to do.
Till may 2008, I have made up my mind to move USA but right i have changed my mind and decide to move canada. Because in canada We got PR and also our spouse can work. But it is the personal choice.