Let me start off by saying that I take time about 3 or 4 times a year to try to convince myself that a .mac subscription is worth it. However, every time I look into it, I just can't do it.
I think the problem with the .mac service is that you can find almost all of these services elsewhere online, for free...
email, calendars, and bookmarks can all be provided for free by google.com... photos and websites take the form of flickr, photobucket, blogger.com, etc.
The online backup system sounds great, but (and this is off the top of my head), I think that it only has 1-2 gb of storage... I have a 250 gb harddrive at home... what happens to all my other information? how do I choose what gets backed up and what doesnt?
In my honest opinion, as easy and as appealing as the .mac system is, the bottom line is it's $99 a year for something that can be found for free elsewhere...