The battle for free e-mail customers among the biggest providers is heating up. After Google recentlyannounced paid storage upgrades for Gmail and Microsoft expanded Hotmail storage to 5GB,Yahoo announced Monday that its own free e-mail service will be getting an upgrade. New features will include built-in instant messaging and text messaging clients, plus faster performance and othertweaks. Like Gmail’s Gtalk platform, Yahoo Mail will now allow users to connect to e-mail contacts in real time through Yahoo Messenger or Windows Live Messenger. To facilitate theswitch to real time chat, Yahoo also made it possible to convert e-mail messages to chats and vice-versa. Free text messaging will allow users to send SMS messages to mobile phones in the US, Canada,India and the Philippines from within the e-mail interface. Besides the new messaging features, Yahoo also claims its newest mail client will be faster and more responsive than previous betaversions. Search has also been refined to allow more advanced options, such as narrowing results by sender, folder, attachment type or message status. To better integrate Yahoo Mail with other Yahooservices, shortcuts are also available. They allow users to right-click on underlined dates, names and keywords to perform functions like looking up an address on Yahoo Maps or adding an event toYahoo Calendar. To spice up the Web interface, Yahoo also added six customizable color themes. Users wary of new features will be able to keep their preferred interface. “We wanted tomake sure that people have the best possible Web mail experience regardless of their geographic location, preferences or system,” said John Kremer, vice president of Yahoo Mail, in a statement.“So we’re continuing to offer our trusted Yahoo Mail Classic interface.”