The great thing about cloud storage services is that, like email accounts, you don't have to tether yourself just to one. I use a combination of Dropbox, SkyDrive, Box.net, and iCloud on my desktop, phone, and tablet, each for different purposes. This is partly because some services have previously worked better for certain tasks--Dropbox is great for collaborating within a large shared folder for work, while iCloud streamlines my photography workflow. Of course, the services offer varying amount of free storage space and have different file size limitations, which also plays a part in how I use each. Over time, I expect more feature parity between the services, along with innovations from each to stand out from the rest--competition is good--and cater to the ways its users actually use the service.
Some big cloud storage announcements this morning move us toward that goal. Dropbox now allows you to share any file or folder by creating a public link. Previously, only files and folders inside the "public" folder could be shared with a unique Dropbox link, but now you can create (or remove) a public link for any file in your Dropbox folder. The link isn't direct--it points to Dropbox's website, where the person you shared it with can download the file or view it in Dropbox's web interface. Folders with photos show up as browseable galleries and links to videos play in-browser. It's unclear whether these new public links are still beholden to the standing 20GB/day bandwidth limit of shared files, so I wouldn't recommend using it to share an image on Reddit. Direct linking is now available on the Dropbox website, mobile apps, and desktop app.
Speaking of desktop apps, Microsoft's SkyDrive now has a desktop client that works on Windows 7 and Vista. The preview app was previously integrated into the Windows 8 Consumer Preview as a Metro-style app, but now works in Explorer--just like Dropbox. Installation is simple--SkyDrive files store locally in your User folder, so you can't change the SkyDrive directory's location like you could with your Documents Library. Files in your SkyDrive Pictures and Documents folders automatically sync up with your Libraries, so it feels very integrated with Windows.
For Mac and iOS users, Microsoft has also updated the SkyDrive iOS app to run natively on both iPhone and iPad, and released a desktop client for OS X Lion as well. The SkyDrive iOS app has most of the functionality than Dropbox's but also adds permissions settings for sharing and file renaming. Both Dropbox and SkyDrive have 300MB file size limits when uploading with a browser. From the desktop, Dropbox allows uploading files as large as your account size can handle, while SkyDrive's desktop synced files are limited to 2GB.
New SkyDrive accounts created today get 7GB of storage, while all previously-created SkyDrive accounts can upgrade to 25GB for free. It pays to be an early adopter, but you'll have to log into SkyDrive to opt-in to the limited offer.