You can even edit video in your web browser now, which could come in handy on a Chromebook or a friend's PC. Sure, WeVideo has some limitations by its very nature—especially on free accounts, which severely limit the resolution, length, and editing capabilities of videos—but all in all, it's successful and straightforward for what it is.
The Dropbox integration and deep collaborative features are especially nice touches, well-suited to a cloud-based video editor. If you plan to use it semi-often you'll definitely want to spring for a premium subscription.
On the other hand, if you just want a simple video creation tool, check out Stupeflix. You can make an unlimited number of videos up to 20 minutes long, and after you add your chosen photos, videos, text, and music, the service handles all the editing for you.