There are tons of features associated with Yahoo's free email program. They recently changed the format and appearance and now the free email on Yahoo is even easier to use. You can purchase larger mail boxes and what not, however for people needing a simple email account Yahoo is the way to go.

Yahoo is one of my main accounts besides gmail. I like it since it is easy to use and accessible anywhere including public computers that are pre-programmed. Easy to search through for old emails and contact storage is easy enough. I don't like the fact that yahoo seems to attrach a lot more spammers than other email providers. While the filters do catch some, a lot still makes it into my inbox which is annoying.

I have used Yahoo free email for quite a few years. I have a few friends that really dislike it but I love it. First it is free. That is a plus. Second I have not ever been unable to access it. I also use Hotmail and have had many times that that service was not available.
I also seem to get much less junk mail with the Yahoo email account over Hotmail (which my box is full of spam).
I know this is rather silly but I also love the goofy little faces yahoo has for you to add in your email. They are adorable!