Cloud is a magic tech word today. "i" has been a golden prefix in tech for over a decade. iCloud, the holiest union of the two, could be the future of computing. For now? It's super convenient! But that's it.
All cloud everything is computing's future. All of your stuff stored where you can get to it from any device, anywhere. No syncing. (Or rather, invisible syncing.) No muss. Never worrying about folders, ever, ever again. Never having to sweat backups, ever, ever again. And for a company that's puffed up its chest over and over and over as the emperor of simplicity, Apple's flight into the cloud should be great. We want it to be great.
iCloud's not one of those "It just works" bolts of lightning from Apple. It duplicates a lot of what MobileMe did before. Signing up is easy—you just power up iCloud, for free, with the Apple ID you probably already have. But from there, you've got a blizzard of sliders, toggles, and settings ahead of you. (Be ready to punch in your password again and again across devices, between iCloud and iMessage.) You'll need to enable it on your phone, decide what you want synced (calendars, contacts, photos, oh my). You'll need to do the same thing on your computer, and anywhere else you want the data beamed. Between the system preferences, iOS settings, and website, there's a lot of configuration—no one-stop-shop for controlling your cloud. It's less than elegant, but once triggered, requires no maintenance or monitoring. On the other side of that coin, if you're used to maintaining fine-grained control over how your data changes and is updated, as you could with MobileMe, that's totally gone with iCloud. It's totally invisible, even if you do want some visibility.
If you go through the effort, iCloud will give you a worry-free backup net, as advertised. Mostly. It'll suck your contacts, calendar appointments, email, app data, and everything else on your iOS devices, safely into some giant data center in the sky. In case of gadget disaster (phone in the toilet! stolen iPad!), you'll be able to retrieve your settings from any computer, anywhere, and restore your replacement like a creepy clone of a dead loved one. One of us did it with an iPhone 4S, pulling in the previous iPhone 4's settings perfectly. Downloads show up on all your devices, perfectly. When it's on, you're imbued with some nice peace of mind—the knowledge that Apple's handling things that used to be a pain in the ass for you. I don't ever have to think about syncing my iPhone, ever again. That's a great feeling.
It's also genuinely smile-inducing to delete a contact on iCloud.com and watch it vanish from your Mac's Address Book and iPhone contacts. Or to steal your friend's phone and rename them with Siri, then watch them get annoyed when they show up in their address book as "Baby." The whole thing's not totally seamless, but iCloud helps rake together the data leaf pile we're all a part of now. And we all need that.
Oh, and it's totally free, unless you need more storage.
As it exists right now, iCloud's missing some major chunks. Why do I have to migrate my entire life from the calendars I use now to a new iCloud calendar? Why can I edit Pages documents between my phone and my iPad, but not pick up where I left off on my Mac? And why the breezy hell does Photo Stream, the vaunted picture sharing component of iCloud, only sync and spread what I've snapped in the past 30 days? If I lose a phone I've owned for a year (or more), I care about a lot more than what I've seen over the past few weeks. Furthermore, why can't anything be deleted off of Photo Stream? It's... creepy. Just hope you don't accidentally sync something scandalous, because, tough shit.
And if you're coming from MobileMe, there's definitely stuff that'll be missed: syncing settings from your Mac, like you could with MobileMe. Or how about instead of shoving iDisk into the background, Apple revamped it into something that worked as amazingly as Dropbox? There are other random holes too, like no Snow Leopard support (at least not yet).
Overall, iCloud's a little too wispy—too filled with gaps and not-quites and almost-awesomes, to be the start of the post-computer epoch just yet. Again: it's a convenience service. A limited one that's free. But something that's meant to ease shouldn't come with its own frustrations.
It's free and useful, so, yes. It's not the glittering future of everything yet, but it's a fantastic, free backup service. There's no reason not to flip on no-brainer backups like app settings. But if you're looking for a simple switch that'll simplify everything—a Steve Jobs "boom" moment for everything on every device you'll ever own—it isn't here yet.