You can create a photo gallery very easily. The photo gallery works very well in case you intent to add a gallery to your article with let's say 10 to 50 or 60 images. You can add more (in fact, it is not limited ...) , but this might be inconvenient for the user to navigate through the gallery. In the future a connector to flickr and Google Picasa is panned where you also can manage big photo galleries.
But to set up a gallery very quickly and add the gallery to an article this feature works like that: Upload all your images to the image library. It might be a good idea to tag all images for instance with the name of the new gallery. Create a new article or edit an existing article where you intend to add a gallery and click then on the small icon in the toolbar of the HTML-editor (in this screen marked red):
In the control of the image library you can filter images by tags (see 'Filters'). You have a preview on the right side. In our case we would like to create a photo gallery like 'Quicktour'. Check the check box 'Image gallery' and select all images with CTRL or SHIFT:
Click 'Insert' and all selected images appear as thumbnails in the HTML-editor box. You can change the order of the thumbnails (Drag/Drop), or you can combine the photo gallery with text and other images or media files. Here you see an example of the photo gallery 'Quicktour':