Google rolled out its monthly Glass update today, adding four new features to the experimental hardware: sound search, photo vignettes, and some integration with both YouTube and Google Apps. Sound search is essentially a voice-controlled version of the song-identifying Google Play widget found on Android. If you're wearing Glass and hear a song you like, just long press on the touchpad then swipe forward to launch sound search. You can also long press on the touchpad and then say, "OK Glass, what song is this?" to activate the feature.

Vignettes on Glass allows you to superimpose a small image of the app you're currently using on top of photos you take, giving viewers insight into what you were doing at the Glass taps into Google Apps for the first time time the photo was taken. The update also adds YouTube videos to search results — and yes, if you want to, you can watch any of these YouTube clips on Glass' diminutive display.

Lastly, the September update allows Glass users to connect the device to Google Apps accounts — good for corporate users who don't want to tie the device to a personal email address. The Glass team warns that Google Apps compatibility is still in the early stages and won't be bug-free, but basic features like email should be working.