How can my eCommerce site use RSS feeds?
Ok, so this answer is probably too simple. But the important thing here is that you've got a blog talking about all the neat things you learn about your own products as you add them to your site, get feedback from customers or (better yet) use them yourself. Nothing beats personal experience, and if you can relate that to your customer well, you gain credibility. Plus, a well done blog gathers subscribers over time and those are "trusted" feeds, so you don't have to worry about SPAM filters when delivering your message to potential customers.
Yes, a new products page is very important to have on your site. I've seen people question their usefulness, but to me there is no better way to get bots to index new product quicker. We maintain our new products page (in an automated fashion, of course) here, and it gets crawled more often than most of the category pages on our site. This gives your new products a boost immediately.
But doing a feed (we did an ATOM feed for some reason at http://www.toolbarn.com/atom/ - not sure why we chose atom, it just fit the model we originally built and I haven't edited it yet) can get bots more interested as well, and some customers enjoy seeing new products via their RSS readers. This also gives our purchasing and merchandising supervisors an opportunity to QA the products being added.
Sales / Specials / Promotions
If you have a lot of specials and / or sales - any type of promotion - that you change up regularly, consider syndicating them. People who subscribe to those are very likely to respond to your offers, and response is what you're looking for. We've been working on this one for a while, but our promotions are all goofy and tough to syndicate - but that won't stop me from moving forward and getting that done.
I've given out a few suggestions here, but if you get really creative you could easily have hundreds of unique feeds going. Just make sure you keep them updated in an automated fashion or the benefits will be outweighed by the effort of updating those feeds. Something like an accessory feed or a related product feed on an individual item could work well. Or a "Hot Products" feed perhaps. There really isn't anything you can't create a feed for, and it only takes that one right person to subscribe to make it pay off.