HTML5 Equivalent to Silverlight RichTextBox?

I've had some experience with the new RichTextBox in Silverlight 4 and I was wondering if anyone knew of a good equivalent/example in HTML5?

I've seen this pretty cool example with contentEditable, but I'm wondering if there are better solutions for creating a rich text editor from scratch out there? I'm really just in my research phase right now and want an editor that can be used on multiple platforms (since I won't be able to开发者_开发百科 run my Silverlight App in iOS, etc). I'd prefer not using 3rd party software/solutions, I'm just looking into the HTML5 options similar to whats out there for Silverlight.

There are a number of HTML-equivs such as http://ckeditor.com/. Is this what you're looking for?