Here's my real world experience with my MobileMe account:
The #1 reason I got a MobileMe account was because I take lots of photos and videos with my Canon Powershot and I like to share them with my friends. The videos are particularly popular with my friends but the files are rather large. If I post a video to a service like youtube, I usually lose image quality since they are lowering the resolution to shrink the file size when you upload. Plus a lot of services charge more for storage space or the ability to upload videos (e.g. I used to use Snapfish which was totally free until I wanted to add videos). When I tried MobileMe, I discovered that the video quality is excellent, folks can easily view the vids and even download them without a loss in quality. Also, publishing a new album of photos and vids from iPhoto to MobileMe couldn't be easier. I highly recommend that you take a MobileMe trial and post a photo album of pics to see how easy and nice it is.
So the combination of iPhoto and MobileMe is a winning one for me. Of course, now my friends want me to post to Facebook, but I simply post a link to my Photo Gallery on Facebook and let my friends download the photos and vids that they want. Then they can choose for themselves what to add to Facebook.
As for the other features...
Mail - I don't really use my .me email address that much. I have a main email address that I have been using for years and didn't feel like making the switch. But I noticed that things don't get spam-filtered as much as when I use my main aol account. So, sometimes I find the MobileMe mail works better for me. I probably should switch over...
Contacts - I do sync my Address Book on my mac with MobileMe, but you know, I almost never go to MobileMe to look up a phone number or whatever. I have my iPhone for that. It's nice that it's there but not essential.
Calendar - I don't really use my calendar. At work we use Lotus Notes' calendar but I can't sync it up with my iPhone or MobileMe, so I see no point in maintaining multiple calendars. I do all my calendar stuff in my work calendar.
iDisk - I really love the storage space that comes with MobileMe, as exemplified by my extensive use of the photo gallery. I even have upgraded my storage space cause I wanted to be able to add tons more photos and vids. I also like being able to create webpages with my iWeb, which makes use of the storage space in my iDisk. For example, I created a webpage of the music I recorded that is complete with downloadable links to my mp3 files (of my original music). And if I want to send my friends directly to the folder in my iDisk that stores my music, I can do that too. And I can send them a link to a single file, though I don't do that very often. I usually just give them access to the whole folder.
So, I don't use all of the features of MobileMe, but what I do make use of works really well. I'm happy with being a MobileMe subscriber. If you own a mac, you really should get it. It's a perfect companion to the iLife suite of programs.
One thing to note: Since I have a PC at work, I've learned that using MobileMe on a PC using Internet Explorer doesn't always work well. MobileMe prefers Safari or Foxfire. You might find that a bit annoying if you are predominantly a PC user using IE. I hate having to switch browsers just to go to different sites.
Hope this helps!
