Actually RSS can be a important tool for
SEO. For one it gives you something else to submit to places you would normally not submit to, such as rss directories. These directories often list each update of your feed, giving some deeper one-way back links.
There are also many sites were you can plug in your feed, such as Mybloglog, even blogger has a widget, so many places. Here again, another place that lists each update of your feed for even more deeper back links from big powerful sites.
Many social networking sites produce feeds from your profile, which could be submitted to places such as pingoat and bring the SE's crawling faster.
Just a couple reasons to put some effort into your RSS feeds. It's done wonders for me.
Also RSS is not just for blogs. I added an RSS feed to my digital downloads store. Updates every time a new product is added. Many of my customers also keep updated about new products through my feed, plus no worry about it hitting the spam folder as with e-mail marketing.