Hi Adam,
Thanks for the answers provided to 3 and 4.
I have a followup question for Item 5:
I am already a user in my application. I have 4 windows including chat in a single page, which I can manage at client side js. And the chat window will be defaulty hidden (not closed, just hidden) (we are using google windoo api for this). When I am to receive to a message from another user, is there any way that I get to know whether the message has come. Anyway It will show the message if I click on the chat window. But without clicking on the chat window is it possible to alert the user in any way that there is a chat message to be read.
Please let us know if you need more information.
Thanks