If you use Gmail to subscribe to mailing lists, you'll love the new 'smart mute' lab feature and the new ways to unmute conversations:
First up is “Smart Mute,” a new Gmail Labs feature that helps solve the problem of conversations that just won’t die. You know the ones I’m talking about: those emails with 10+ people cc’d where everyone replies all, but you lost interest five emails ago. The current mute behavior doesn’t do well in these situations since the messages are addressed to you. You end up with muted messages in your inbox, and the only way to prevent these emails from coming back to your inbox has been to create a custom filter for a specific conversation.
Since you’ll likely be muting more than ever, we also added easier ways to unmute muted conversations. Previously, the only way to unmute a conversation was to move it to your inbox -- not super intuitive and useless if the conversation was already in your inbox. Now there are two new ways to unmute a conversation. The first is through an "Unmute" option in the "More actions" menu. You’ll see this when you view or select a muted conversation.
If you’re viewing a muted conversation, you’ll see the second new way to unmute: the "Muted" label next to the subject line now behaves just like all other labels. Clicking on the "X" will remove the Muted label and unmute the conversation.