Whatever the future of HTML5 gaming holds, the present of (2D) HTML5 gaming looks pretty bright.

Here are three tools for helping you develop HTML5 games right now, each offering something different.

• GameMaker: oldest and most powerful. Recently added HTML5 support (costs extra). Lets you create simple games without writing code, but the visual interface generates code in a pretty slick, vaguely C-ish scripting language (GameMaker Language, GML), which you can then edit manually. GameMaker's biggest strength lies in GML, because it's hard to create complex games using just a visual interface. Free 'Lite' version available.
• Construct: simplest and easiest for basic games. Just added WebGL acceleration. Freeware for games with <100 events. Includes drag-and-drop physics engine.
• Spaceport: not its own game-making system, but rather a way to create HTML5 and JavaScript games once, then turn them into native apps for iOS and Android. Also converts existing Flash games (through the website).

Recently a friend of mine, who did serious AI and natural-language programming for the military, lost his job due to massive downsizing..and now he writes web games, because (he says) it's a relatively safe market. So maybe, even if you don't currently work in game development, experimenting a bit with simple web games -- especially games that use new web standards -- might be worth a few minutes' investment.