RazzMaTazz
Android Expert
Thanks for the comments and link.One thing to consider as an advantage for Gmail is if she ever decides to use Google+ is it's tighter integration with it (note the new Google bar (black) for Google+ users that integrates major Google assets) as well as if she's using an android phone. I've used Gmail since it's inception and have not had any issues with it, especially since I use it for my personal life while I use Outlook for business and try to keep them separate.
Here's an article (last year) that compares Gmail and Hotmail.
How Does the New Hotmail Stack Up to Gmail?
Unfortunately, the article comparing Hotmail to Gmail focuses on the webmail-based interfaces and features, all of which are pretty irrelevant to those of us using Outlook and Android.
It will be interesting to see if Google+ (i.e. Google's new Facebook copycat) will become relevant and if it will integrate its assets in such a way that provide advantages to people who use Gmail instead of Hotmail or Yahoo mail, or their ISP's mail service. I'm skeptical.