Well, after dealing with poor customer service (4 business days to receive a response is not acceptible) via email, I was able to stay off Yahoo Mail for a week. Did I miss anything? Not at all. I will be switching a few subscriptions over for commercial interests, such as Borders Rewards coupons, but the rest is pure crap. In fact, here's how the last week's worth of email that made it into my inbox breaks down:
Yahoo Groups & Freecycle: 4
Of the 65 total messages since last Saturday, one third were pure spam, including a few "PDF" attachments via the spam message that are actually viruses. Wow.
I've had my Yahoo Mail account for years now... it's going to be sad to see it go, but it's so much like walking away from a bad habit that I'm going to be relieved to not have to deal with a tool I don't really use or need. One down, several to go.