Adobe Thursday turned its little piece of Disneyland for developers loose.

The pre-release of Flash Player 10, a k a “Astro,” which promises richer, more immersive Web 2.0 experiences, has gone to public beta ahead of general availability sometime later this year.

It adds custom filters and effects, native 3D transformation and animation, extensible rich text layout and GPU hardware acceleration. Adobe thinks it’s a game changer about what can go on the web.

The custom filters and effects come compliments of the free Hydra toolkit – now officially called Pixel Bender – that borrows from Adobe’s After Effects CS3 software, an industry standard for creating motion graphics and visual effects for film and broadcast.

Developers can create their own filters, blend modes and fills by writing small pixel-shading functions to create movie-like animated effects or morph the effects on rich media content at runtime without slowing down performance.

It can offload the work on to the GPU, freeing up the CPU to render 3D content and sexy effects and process complex business logic. Adobe says no other browser runtime can do this.

The widgetry will rotate and support ligatures in fonts; allow vertical, bi-directional and right-to-left text layouts and ultimately automatically adjust video quality if bandwidth fluctuates to provide constant video playback without pausing to buffer.

Adobe said Flash Player 10’s innovations will show up in AIR and its new Open Screen Project, which is set on delivering a consistent runtime environment across PCs, mobile devices and consumer electronics.

The beta works with Vista, XP, Windows Server 2003, 2000, Mac OS X and Ubuntu. See www.adobe.com/go/astro and www.adobe.com/go/pixelblender. Demos are at www.adobe.com/go/flashplayer10_demos.