Okay, minor pet peeve. I've pretty much switched over to using Outlook as an RSS reader to keep up with journals of interest. I still get a few ToC by email, but the RSS mechanism has lots of advantages. First, I'm in Outlook all the time, so it's a natural place. Second, I can leave behind copies of the papers of interest, with all the tools in Outlook for moving them or tagging them & such. One minor annoyance is you can't (as least as far as I can tell) force a scan of the RSS feeds. Sure, mostly this is obsessive or time-killing, but when you have intermittent net access it's really handy.
But one big difference in the feeds. Most ToC feeds send out one entry per article and that entry contains the title, authors & abstract. But PNAS sends out only the authors, title & a very short head end of the abstract. Aaaaarrrrrgggghhhh! Lost is much of the ability to vet my level of interest in an article plus the additional keywords which would enhance searching for it.
I realize PNAS is already busy with torquing their acceptance channels, but could someone who knows someone there in power please get them to fix this?!!?