For now you can only view album art in the file display itself (not the viewer pane), when in thumbnails or tiles modes.
Editing album art can be done to some degree by creating buttons/hotkeys/menus which use something like Album Art Aggregator (see this thread or my WmaAlbumArtist tool (see this thread). More integrated album art editing might come in a future version.
AFAIK nobody has requested (at least here on the forum) that the viewer display album art, but it wouldn't be difficult for someone to write a plugin which did that, or you could send GPSoftware a feature request to see what they think (but their list of existing suggestions is very long, of course, but it doesn't hurt to ask).