At least to me, who sees what's under the skin.

The "HTML" version is basically the first version of the software, which output the simplest of monolithic Web pages--the TOC and the surrounding decorations are an integral page, and when you click on a message title, you go to the message as a Web page whole and complete. The only JavaScript on the page isn't critical in case you have JavaScript turned out, the use of a popup message form instead of, again, going to a whole 'nother page to fill out the message form. HTML mode is basically the least-common denominator, and ought to work on any browser ever made since about 1996.

When I did an extensive makeover in 2003, I retained the old output system, and added the system for the "Nexus" in parallel with it. The Nexus is a lot more efficient, because it keeps one page around the whole time--the outer page with the title and the graphics and all that--and switches the TOC and messages in and out of the central "arena" element. The Nexus relies extensively on JavaScript, and that's sometimes been its downfall, as that makes it more vulnerable to cross-browser differences. The script does such things as switch graphics in the header and menu when you switch boards, which is a lot faster than reloading an entire page; and controlling the notorious "Earlier" and "Later" buttons, and not too well.

The software on the server, in Nexus mode, outputs lots of small HTML files, including many like the TOC that are only fragments of HTML. The fancy Nexus user interface gets its efficiency from putting together those little bits to form the screen that you see. The Nexus mode on the server turns out to be well-suited for the next generation user interface, so I'll have the advantage of not having to mess much with all that old code. The latest razzle-dazzle "Web 2.0" technology goes further in the same direction of working with little bits and pieces of stuff assembled into mashups, so it's a natural fit for a Web 2.0 UI to keep working with a server side that already produces little bits and pieces.

"When?" you ask? Or more like "For god's sake, when will you stop talking about a next generation HabitableZone and just !#@$!@ing get down to work building it???". I'm tired of hearing that question coming out of my own superego, too. Finding a credible answer is difficult because the Zone, while being at the top of my emotional list of things I value, doesn't put bread on the table, and thus it necessarily gets forced to the bottom of the list of things I have to do. Being dependent on the business of geekiness, recreational geekiness is most likely to flower after the end of the next large paying gig, when I have free time to indulge myself. In the meantime, I think about the problem regularly, usually when something in the foreground suggests something that would work on the Zone, and I file it away in an ever-growing feature list. When I finally get a chance to work on it, I expect it'll unlease a tsunami of stored-up ideas.

You should see the HabitableZone that I see in my mind's eye! It will absolutely knock your socks off...someday.