[degenerate]

Yes it suspends the process, but doesn't visually indicate this by fading/sorting the tabs for you. At least, not the version I used a year ago. (edit: it does now!)

[dreen]

For me it fades the favicon slightly

http://i.imgur.com/y1xSEtF.png

To be fair the suspend feature is the killer here

[noxToken]

It visually indicates it by replacing the site's favicon with the app's icon. If you see blocky face, your tab has been suspended.