Me too. Gmail is for people I trust, yahoo is for when I want the email but don't want the sender to have my "real" address (e.g. hotel/travel confirmations), and hotmail is for when I don't even want the email.
I use Yahoo mail for signing up to things. I check it once or twice a year. I have a flickr account but wouldn't notice if it disappeared. I use Yahoo site explorer for SEO tracking though, and that's useful. I also use Delicious more or less daily.
I'm still angry that yahoo bought them. Since then they've let flickr stagnate while the rest of the landscape innovated around them (almost making them obsolete) and they've added the encumbrance of being forced to login with a yahoo account.
I tried to sign up for Flikr and noticed Yahoo had bought them. Refusing to sign up for a Yahoo account, I now use Picasa for photo storage and sharing.