Gregory Menvielle, the CEO and founder of Pyramedium, recently offered up some insight into last month’s HTML5 Developers’ Conference. Not only did he offer those who couldn’t attend a good idea of what they missed, but he also posited that the focus of the conference seemed to indicate that HTML5 has finally hit its stride.

To support this, Menvielle cited what Intel VP Christos Georgiopoulos said during his conference keynote: Based on the Gartner (News – Alert) Hype Cycle, HTML5 has made it to the last stage, the “Plateau of Productivity.” This means HTML5 has made it past the trying first four stages — the Technology Trigger, Peak of Inflated Expectations, Trough of Disillusionment and Slope of Enlightenment — to reach mainstream adoption.

Indeed, according to Menvielle, the fact that the conference focused more on overcoming the challenges of bringing HTML5 to the mainstream, rather than helping it gain acceptance, seemed to confirm this. Other takeaways from the conference include: the importance of visualization, how the promise of HTML5 shouldn’t be taken at face value, and the HTML5 connectivity problem.

In terms of visualization, the challenge going forward will be to figure out how to visualize data in HTML5. Fortunately, some frameworks with this goal in mind have already started to hit the scene.

As for HTML5’s promise, Menvielle warns that deploying HTML5 on mobile devices is “much harder and convoluted than deploying on the Web.” As such, many companies aren’t properly prepping their mobile deployments, which could affect HTML5’s chances in the long run.

Finally, developers need to start considering what happens to their HTML5 apps when not connected to a network. This problem also has to do with proper planning, specifically in terms of how to let users use an HTML5 app securely in a disconnected state.

Menvielle didn’t attend the HTML5 Developers’ Conference just as an attendee, but as a participant as he was asked by Intel (News – Alert) to take part in its keynote and talk about his SmartNotify HTML5 app. Intel, meanwhile, has been getting more serious about HTML5 lately with the release of its new XDK HTML5 cross-platform toolkit.

For those unable to attend the conference, there’s still a chance to see what the HTML5 space has to offer at DevCon5, set for Dec. 10-11 at Universal City, Calif.