Also mentioned was this quote:
Silverlight also has some “sweet spots” in media and line-of-business applications, he said.
News media frequently twist facts, or mention only selected facts, as a way of making the story better. Silverlight is not dying off, and the HTML5 spec has not been ratified.
One could also draw the conclusion from that article that MS are doing their best to manipulate the HTML5 spec to suit themselves and we will end up with a situation like we had in the past: everyone implements the same spec in a different way and you need to code workarounds for each major browser. Because of this wrangling (which other vendors will no doubt also be doing) it may take a long time for the spec to be fully ratified.
Having said that, WPF is not subject to any of this uncertainty - but it still isn't cross platform. So you have to ask yourself these questions:
- what is the expected lifespan of your LOB app?
- how long before it gets a major rewrite?
- is it possible to release it in several different technologies to suit different setups?
LOB apps tend to be quite tightly spec'd and controlled to specific setups, so a long term change of focus for Silverlight may not affect you that much at all.
EDIT: the day after i answered this question, Colin Eberhardt wrote this very good blog post: Does HTML5 mean the end is in sight for Silverlight? which covers this exact news story / quote.
Colin also references this follow up blog post from Bob Muglia1 which elaborates on what he was quoted as saying. I think you can safely conclude that it is absolutely fine to develop your LOB app in Silverlight if you want to :)
1 President of the Server and Tools Division at Microsoft