The one true casualty of RSS aggregation will be visitor traffic numbers to a blog or website. But, with the statistics tools available from Feedburner and other RSS creation sites, this is the least effective of the arguments available for those pushing partial-text feeds. All they need to do is take the number of visitors to the site and, using an old-fashioned calculator, add to that the number of subscriptions to their RSS feed. It's as simple as that.
I say full-text feeds. Businesses have to give consumers what they want. And they want full RSS feeds. You can't hold back so that you get more site traffic.
If anyone out there works for an RSS reader, I have a business plan floating around to design a new one with a lot of technological features inspired by A.I. I haven't been able to find funding for it (I think most people I've talked to don't even know what RSS is, let alone A.I.) so I'm willing to give up the ideas to someone else. I'd just like to see it implemented. I've moved on and am focusing on another project.