We are using this to display our org charts, but we need something that supports:
Are there any competing tools that give better support for the above.
G'Day ooo
I'll keep this short. No there isn't. Not with Javascript anyway. You might find http://www.cogmap.com/ interesting but it's not something you can use as a control on your own pages.
Personally, I'd be looking at some of the rich embedded media like Silverlight or Flash. Is that an option for you?
Cam
In short @Cam is right, but you don't necessarily need to look at Silverlight or Flash. I would recommend looking into the Raphael.js library. It's more low-level than what you seem to be after, but the API is pretty simple.
In particular the Graffle example would be a good place to start.
If you're looking for alternatives that works as a service like google does, I don't think you have any. If you're looking for libraries (js, php, flash) that can create these charts for you (you can install the libs in a server, and create a simple interface to create the chart objects) you can search for older posts in SO or by searching some blog posts in google.
If you're only interested in an Org Chart creator, just to get the work done, nothing beats Creately's solutions in my opinion. If you need to create just one diagram, and don't want to pay for it, you can use Lovely Charts.