The basic layout of Lightroom's interface is pretty typical of an organizer: thumbnails along the bottom, with keywording, metadata, and filtering tools around the sides of the screen, and larger previews in the middle. Unlike most organizers, though, Lightroom's Library module has some quick retouching tools, too.
Though I wouldn't call it skinnable, the interface is modestly customizable; you can even replace the product logo in the upper left-hand corner with an Identity Plate.
It's very easy to roll your own Identity Plate, as long as it's text-based. Lightroom even allows you to choose a font for the module navigation.
I was less impressed with Lightroom's handling of graphics for the ID Plate. It doesn't support PSD files, just Web bitmap formats like GIF, JPEG, BMP and PNG. That makes using transparency tricky. If the ID Plate were just for your onscreen work space, it wouldn't really matter. But Adobe gives you some cool places to use it, and the lack of proper transparency support becomes an annoying drawback.
Though Lightroom references all your files from whatever location you prefer, it needs to import their locations into its database. Its photo downloader is really quite nice for this, and provides ample flexibility for programatically downloading, tagging, and importing photos from removable media. If you click Show Preview, a dialog displays thumbnails of the photos, allowing you to choose only selected items to download.
Aside from the standard random thumbnail view, Lightroom offers two very useful layouts. My favorite--an n-up view which lets you view any number of non-contiguous images simultaneously--doesn't have the toss-'em- anywhere quality of Aperture, but I like an organized work space. When you discard an image from the view, the program automatically realigns them to maximize the preview sizes.
If you used an early beta of the program, you might remember the ability to group photos into Shoots. Well, that option's gone in the shipping version, replaced with more traditional Collections. Thanks to the ability to save custom sets of keywords and metadata, tagging images from repeated shoots in Lightroom is incredibly easy.
In the Develop module, there are many different ways to adjust tonality and color--one might say too many, but I suspect that no two people perform adjustments the same way to get the same results. You can save your curves as presets, which becomes essential for printing from Lightroom. In Develop, you also can crop, straighten, remove red-eye, and heal blemishes.
Lightroom's white-balance adjustment tool is excellent. Not only can you simply click on a neutral area to make the fix, but the program provides a zoomed view of the vicinity of pixels from which to select. This is very important in digital photos, where even areas of flat color can have variations at the pixel level; this way, you're guaranteed to pick the correct one.
Among the myriad ways Lightroom lets you manipulate tonal values are some direct controls. For instance, clicking in the image and dragging up or down will adjust the values under the cursor, and the changes are reflected in the curve, histogram, and sliders. You also can click on the histogram and drag side to side to adjust overall exposure. Each tool gives almost too much feedback, but you eventually get used to ignoring the info you don't want.
Even if you have established retouching methods, Lightroom's interface can help you discover new ways to do old things, as well as ways to do things that were previously too difficult. For instance, removing the yellow cast from this photo would have been quite painful (but doable) for me in Photoshop; in Lightroom, I practically tripped over this tool with its preset color ranges, and fixed the cast in this photo in under a minute.
With a handful of templates, Lightroom's slide show module is probably the weakest aspect of the program. It produces strictly linear, single-image productions with some nice drop shadows and some custom text--and exports them as PDF files.
Adobe has done some very nice things with Lightroom's printing layout interface, though the color management leaves something to be desired--you can choose from the existing printer profiles on your system, but there's no screen-match preview like in Photoshop. In fact, Adobe makes it quite frustrating for printing: Lightroom has the great layout and captioning tools, which Photoshop lacks, but Photoshop has all the color management and WYSIWYG preview capabilities that Lightroom doesn't.
Lightroom delivers flexible print-layout capabilities in a very interactive, easy-to-use interface. The info in the upper left corner doesn't print, but is a great reminder for those of us who use multiple printers and paper types and frequently forgot to change them before printing.
Lightroom's print annotation skills are the sublime to Photoshop's ridiculous. You easily can build variable statements to print any file, EXIF, IPTC information, numbering, and custom text. You also can overlay an ID Plate, which is where the lack of support for transparency in the graphics files becomes a hassle.