Thanks for you help, I have resolved the issue.
It did look like a corrupted VM upgrade issue, but also a factor is the way VM displays price without or without tax - if different options are selected. It does not display pricing on the cart.
The issue was unrelated to the template.
For others not seeing prices in the cart - check the price display options in VM - if you select prices without tax - you'll get prices in product display but not in cart.
