Zoho notebook -- this looks like an incredible tool !!

I've been playing around with this online notebook (although i haven't had much free time since I discovered this a couple of days ago) and I have to say I am extremely impressed. So impressed, indeed, that I wonder why I haven't been enticed into Zoho some time ago.
(Yes, I did see various references in Lifehacker to Zoho Writer and Sheet as being alternatives to Google Docs).
Zoho provides a very sizable collection of free online apps such as, in addition to Notebook, Writer and Sheet, many others such as Chat, Show, Meeting and more. Check it out here.
The notebook is absolutely superb as I've already mentioned in the last post. One problem, though, is that at the moment it doesn't work so well in Opera (which is my preferred browser) as explained in this forum thread.
Luckily, this omission will be fixed soon.
I tried sharing notebooks which "sorta" worked but was not perfect. For example, the sharing notebook showed no shared notebooks although the unique invitee did show a notebook as being shared which showed up without problem.
However, when I added an object (a .mp3 file) to the notebook being shared, it just didn't show up on the invitees view of the notebook.
In addition, although I had shared the notebook giving read&write permission to the invitee, anything that the invitee tried to do was greeted with a pop-up announcing that permission was not available to add objects to the notebook.
I have no doubt that this is due to my browser choice. Looks like for the moment I'm going to have to use Firefox to experience Zoho which I'm very excited about.
There's also the Zoho forums which I'm going to have to get involved in.

Edit (23-08-08):
I've just tried zoho notebook sharing using Firefox 3 with Ubuntu 8.04 sharing with Foresight invitee. It worked flawlessly. In particular, I was able to add the same .mp3 file to the shared notebook and it almost immediately appeared on the invitee's screen and could be played without problem. Indeed the same song could be played on the sharers computer at the same time.
This is fantastic.
As a lot of my friends use Windows, I'm going to have to look at how easy it is to go cross-platform with Zoho notebook (and the multitude of other Zono stuff).