I've been watching SilverLight on the horizon for a while now, with the same defensive dread I view the introduction of a brand new browser: It'll mean pain eventually.

Silverlight directly attacks Flash in terms of its niche and capabilities; that is, Flash + Flex, Adobe's programming framework for Flash applications. I'm pretty sure it's in no way compatible with Flash, so that I wouldn't worry that it'll yank away the .FLV and .SWF file types recognized by Flash. Microsoft aims to take away market share from Adobe, not grow Adobe's market. Typical divide-and-conquer strategy.

MS is giving away the support plugin for SilverLight, and looking to make their money selling extremely expensive developer software. You'll have to drop a minimum of $500 to start creating SilverLight, and near $1000 for the full suite (matching Adobe chutzpah for chutzpah in excessive pricing).

That won't change any time soon. In contrast, Flash has been around long enough that there are now open-source Flash developer's tools, notably OpenLaszlo. And Adobe gives away the current-minus-one version of the Flex SDK.

Bottom line, I see nothing at all about SilverLight that suggests that Microsoft is breaking any new ground or innovating in any way. They're just copying Flash, and redesigning it to be dependent on Microsoft developer software.

Watch for Adobe to one-up Microsoft by submitting the Flash formats and protocols as international standards. They did it with PDF at a time when Microsoft thought its RTF would be the standard for document interchange. Open source and standards are alien to the Microsoft DNA, and slowly but surely, Microsoft is becoming marginalized. SilverLight may someday be seen in retrospect as one of its last gasps and grasps for proprietary control.