I chose javascript/jquery over flash for several reasons. My goals are to make Hal work on as wide a variety of devices as possible and since iPhone/iPad don't support flash, html/javascript was a good choice. After this character is up and running on the web page, I will make an app version of Hal using software called PhoneGap. PhoneGap lets you write an app with html5/javascript and then packages it like a native app for all mobile platforms. So I'll just need to write it once and can deploy it to Android, iPhone, Blackberry, and Windows Phones.
Secondly, I'm trying to avoid use of closed proprietary software as a base for Ultra Hal as much as possible. Hal still has a huge code base written in old VB6, which is a closed proprietary system that Microsoft discontinued many years ago. After being burned by Microsoft's killing of VB6, I've been very wary of rewriting Hal under VB.NET or C# (VB.NET is a rewrite, not a continuation of VB6). I didn't want to be burned again if Microsoft decided to stop supporting .NET. So much of what I've written since then has been based on open source tools. The Hal running on my servers use open technologies such as MariaDB, Sphinx Full Text Search, Debian, PHP, Festival.