After 18 months of Gmail Labs being in operation, Google's killing off some unpopular features, but also promoting the oft-used ones to permanent functions. Say hello to the forgotten attachment detector, YouTube previews and custom label colors.

While the muzzle, fixed width font, email addict, location in signature and random signature functions have been buried by Google due to either a lack of interest or the feature made redundant by something better that's waltzed on in, at least the good man won, with my trusty forgotten attachment detector graduating to a standard feature.

It detects phrases in your email, such as the word "attachment," and before sending the email reminds you of the forgotten attachment. Definitely saves redface, especially when applying for a new job.

Search autocomplete and the go to label function will suggest words when searching in the Gmail box for a particular email. YouTube Previews is fairly self explanatory, opening a little preview which will avoid being Rickrolled for the umpteenth time.

Over 4,000 colors are now available for labels—handy if you have a green fetish—and the last graduating feature is vacation dates, which will turn on your out of office autoreply based on what dates you're on holiday. [Gmail Blog]