Google is partnered with TrueSwitch and start rolling out a new migration tool in Gmail. If it's not there yet, then you'll have to wait until it's available for everyone. Once it’s available, it will be much easier to migrate from most popular mail services (AOL Mail, Yahoo Mail, Hotmail and many services provided by ISPs and mobile carriers) to Gmail and that could the increase the adoption of Google's mail service. The new option should be added to the new Accounts and Import tab from Gmail's settings page, reports InformationWeek.
“If you're switching to Gmail from another email provider, importing contacts and messages from your old email account can help you make the transition without having to do a bunch of housekeeping,” explains Google.
Source:→ Google System