fantastic effort, this is a a great contribution, I will be happy to test with my 8,000 product list or at least part of it.... Okay.. Initial test results with 1400 products timed out, second attempt with 500 was processed but lots of errors repeated.... I included the errors in the attachment... only half dozen errors but lots of repeats

So without categories, each product goes in with no taxonomy applied? I noticed that the drop downs included my taxonomy top level vocabularies under "category" one of them being Product Catalog. Maybe this is close to being able to at least get the products into a high level cat??

The orphan product page in store admin does not offer a method to apply taxonomy to a group of items it only links to the edit screen for that item. The move products allows you to move or copy items between categories, but does not let you move from orphaned to category XYZ

So that being aid the products did import ( they showed up in "recent posts" all 500 but the type -1st column on recent posts- was not "product" the type is blank) when I went to view a product it did not display anything except title & description and when I clicked to edit the product i got the following error message:
warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, '_node_form' was given in /var/www/sandbox_bj/html/includes/form.inc on line 218.

I will try some more tests (perhaps this time specifying a class in stage 1... one of the error messages spoke of required class setting, and my import is not using classes)

Once again thanks for a great start to a much needed functionality... ill keep on testing