Take for example editing and selecting. CS2 Bridge was seriously flawed because you couldn't magnify your images to 100% to check for image sharpness. You could go into Adobe Camera Raw and magnify a set of images there, and some photographers did just that and used ACR as a editing and selecting application. CS3 Bridge now includes a Loupe tool that works very well if you are in either of the Filmstrip views. Just click on an image in the preview window and a small portion of the image is magnified 100%. To increase of decrease the magnification you need to poke the + or - keys.

And then there is way Lightroom does the same thing.

Select an image in the Library module and go to the Loupe view. (Keyboard command E for easy)

Click or press the Space bar.

Lightroom will zoom in to the magnification level you set in the navigator panel.
Click or press the Space bar again and you are back to the normal magnification.

Select the compare view (C for Compare) and now two images are side-by-side and connected like Harry Potter and Lord Voldemort.

Click or press the space bar, and they both enlarge to the same magnification.

Use the hand tool to move the images around in the frames. (You can turn this holy alliance off by clicking on the lock icon in the toolbar)

Bridge, Camera Raw, Photoshop is a viable workflow and I'm happily updating my book. As I've said before, it's like an off-road vehicle that gets you everywhere, albeit a bit roughly. Lightroom is a sports car, sleek, fast, and a pleasure to drive. I'll be driving two cars for a while.