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I bought iLife for iWeb, so that I could create a website for my business. It makes site building incredibly easy, to a simple drag n' drop. I've got audio and video links going, photos, html widgets (but without the need to know about html).
Also, the excellent Garage Band allows the creation of music in what is basically not dissimilar to a very stripped down version of Logic Express (GarageBand files are compatible with Logic).
iMovie is useful for editing video footage from cameras and camcorders - and makes it easy to do. Beware though, editing is slow on lower performance macs.
In iPhoto 11 they've added the face recognition (actually it may have already appeared in iPhoto '09 but I upgraded from iPhoto 08!).
Finally, iDVD. I've never found a use for this but as the overall package was cheap anyway so I don't mind.
This is worth the money if you want an enhanced multimedia experience with your mac.