GMail - any day. More compact, better UI, you can use hangouts also while checking your e-mail, it is synced with Google+ and easily integrated with Google. I used to be a Yahoo fanatic, using Yahoo Mail for many years - but things changed when I stepped upon GMail.
I find it quite amusing the reasons why people still use Yahoomail. Read this post Reasons Why People are Still Using Yahoo Mail?
I've been using gmail ever since it launched, back when you needed invites to use it. I'm not a huge believer in all of the google conspiracy theories, so I'm fine using gmail forever and ever. The only time I use yahoo! is when I need to use flickr or Yahoo Answers.
I prefer Gmail but my primary e-mail is Yahoo! Mail, I guess it is where I have been using Yahoo Mail ever since I first opened e-mail address for e-mail and got too used to Yahoo mail service but I like Gmail service much better.
If your question is just about preference, I prefer Yahoo! Mail over Gmail. Yahoo! allows you to create e-mail aliases, which is very useful. Yahoo! does not force you to allow their systems to check your e-mail words in order to show you advertising. Google policies —including your use of Gmail— are, since 2012, used to gather a profile about you. I am personally against that. I do have a Google account beucase I work in SEO, but I do my best to keep its use to a minimum.
If i should choice between yahoo and gmail, maybe i prefer Gmail, because Gmail have simple appereance .. Not just it, there are many membership provider that recommended to use Gmail When they member signup #it just my oppinion
I agree with chinesegirl, Gmail is wonderful. Clean, easy to use, no spam. Yahoo is cluttered and full of spam. Seems like an easy choice to me.
There is also an instance that yahoo mail server was down for a day. I was expecting an important email from a client when I realize that the client has not replied back to my email. Good things I sent out a message using skype and clients said that they did not received any emails from me.
I just moved to yahoo, because i felt some difficulties in gmails.. But gmail is more user friendly than yahoo..
What difficulties? It seems to work out of the box. Yahoo is usually broken. I switched to Gmail way back during the beta and stuck with it. It works great. I login to the Yahoo email once every few months to keep it active and delete crap.
I use both. But Gmail is more frequently used due to I use G+ and blogger which are automatically connecting each other.
I use Gmail, but I do have a Yahoo account. Gmail is definitely better in the sense of linked applications and services, but as far as the actual mail sense goes I link my accounts in Outlook (not the online version, the Office application) anyway.
Yahoo mail gives you a 1 T.B (1024 G.B) space while Gmail allows only 30 G.B space on free accounts. In terms of memory space yahoo wins.