In the wake of Adobe CFO Mark Garrett's comment that Silverlight's popularity has fizzled in the last few months, and Microsoft exec Tim Sneath's comments rebuking that claim, two developers that voraciously churn out applications using the two platforms said they expect competition to heat up in coming years. The companies are already duking it out for big time customers. Adobe, for instance, just announced that they've signed an agreement with MLB.com to provide Flash video starting in the 2009 season. Last year, MLB.com used Silverlight, Adobe claimed. The company also boasts customers such as MySpace Music, DIRECTV, FOX News, and Disney.com. Microsoft, meanwhile, talks up Silverlight by pointing out that CBS College Sports, CNN, NBCOlympics.com, and Netflix all use the player. 

On the developer side, here's what some folks with experience using Flex and Silverlight had to say:     

FLEX: R.J. Owen, senior developer with EffectiveUI, creator of a global climate application for The Discovery Channel's Website (pictured below):  

"Long term, I think Microsoft is poised to be a huge competitor. I think they know how big a market RIA technology and rich user interfaces are, and if they don’t have the resources to make this work then no one does. I think Microsoft has really learned the value of user experience over the past few years and I think the tools surrounding Silverlight- Blend, etcetera- will both reflect that value and might soon allow us to make just as compelling user experiences as the Adobe tools do. I just don’t think they’re there yet.

"On the flip side, I really appreciate Adobe's commitment and support of open-source technology. Most people don’t realize that Flex today is almost 100% open-source; while Adobe maintains the product, it’s schedule, and deciding what patches get included, anyone can fix bugs, submit patches, and help drive the direction of the language. Adobe’s committed to supporting the technology internally and still has a large support team dedicated to it, but as an active member of the community I’m always impressed with the amount of attention Adobe gives to us. They really use our ideas, and I think we’ve had a strong hand in helping create the product that Flex is today."

SILVERLIGHT: Rockford Lhotka, principal technology evangelist for IT consulting firm Magenic:

"I’m coming at Silverlight from a developer perspective, and seeing that 90% of my .NET code will run on Silverlight without change. I’m seeing my investment in learning WPF translate directly into Silverlight skills. I’m seeing a future where I can write an application that runs on a desktop or on the web, where less than 10% of my code is different to support both environments. This is incredibly compelling!
 
I do understand the reservations from the pure web UI people. They want a technology that has better than 95% market penetration to run their animated ads and seizure-inducing graphics. I suspect that five years from now Silverlight will be closing in on Flash for that purpose, but it isn’t there today.
 
But from a software development perspective, Silverlight enables code sharing and skill reuse from Windows to the web. And it provides a far more consistent and, I think ultimately, lower-cost platform for many AJAX business application scenarios as well. No need to fight with Javascript and the increasing number of browser DOM permutations, because Silverlight provides a much more consistent target environment where I can use my C# or VB skills."