PNG Product Images?

A question to the community at large. I’ve been asked to give an opinion on the PNG file format. More specifically, if it would be worth it to include a PNG version of products in the process of creating web photo assets. Note that I’m referring to a large number of product images (in the hundreds of thousands), so we’re talking about a fundamental shift and yet another step in what can be a time-consuming process.

I’m familar with most of the pros/ cons of PNG and have utilized them for their benefits in gradients and tackled the whole IE transparency issue. The question is, would you bother with PNG?