Google has added group chat and smiley support into its chat window in Gmail. With this you can chat with multiple people using your IM in Gmail. Smiley support is also available with this. Once you select a person to chat, click on options and select Group Chat. From the window, you will be able to add multiple people into the chat by entering their names.
There is also a smiley face in the bottom right-hand corner of your chat window. You can still use regular emoticon keyboard shortcuts, or you can use the rich emoticons styles. There are two brand new rich emoticon styles available.
These features are available only in new version of Gmail, which Google is in the process of rolling out to all users. Gmail has been in news recently ever since they rolled out the new version, they have also made the storage space to 5GB and now planning to release the GDrive.
Via: Official Gmail Blog