I love MobileMe and will probably keep my subscription for quite some time. I love iDisk...it allows seamless portable files & syncing to other Macs when needed. They're really getting much better and I think they'll add functionality for streaming your iTunes library at some point. I share a lot of files over MM in the work I do and it's easy enough for others to drop things in my Public folder. I like the choice of putting a password on file shares/downloads and the ability to expire then.
Most other freelancers I know also have Macs so, for me, it's a great service. If you're surrounded by PC's all day, then it might not seem like a great value. But in New York, I work in entertainment, and the only PC's I see are when I have to go into the corp offices of someplace I'm freelancing at. And even then, half of us are freelancers and bring our MPB's in anyway. (<--- EDIT: I sound like a hipster DB, I know. But it's true. lol)
There was some glitch with syncing calendars but it seems to be fixed now and I've never had a problem w/ my Contacts syncing w/ the iPhone, cloud or GMail. Find my iPhone is a great feature but I'm hoping I don't ever actually have to use it other than when I can't find the phone in my house. lol. I don't use the Gallery as much as I probably should but I have a Flickr account so I find that better for pictures & video. I have both .mac & gmail email accounts. I like using the aliases but still have them all coming into 1 box.
In all honesty, it really all just seamless and I'm paying for convenience as well as functionality. Worth it in my book.