Microsoft already has a much faster Javascript engine in Silverlight, but they would need to make big changes in IE to integrate their next-generation Javascrip

Microsoft already has a much faster Javascript engine in Silverlight, but they would need to make big changes in IE to integrate their next-generation Javascript implementation into it. Besides, the IE team's approach to performance is different than Mozilla's and Apple's approach. Instead of just improving raw performance, they look at entire use cases and try to optimize them for usability and performance. To the IE team, a 50% increase in some artificial benchmark means nothing, but a 50% decrease in the number of steps and/or the amount of wall time for the user to accomplish a task is very important. Here is what they had to say about their integrating their new Javascript implementation into IE: Chris Wilson [MS] (Expert): Q: Why not adapt the the Silverlight implementation of (managed) Javascript and fit it in IE.next? It's fast as hell. A: We've been looking at Javascript engines closely. The transitions back and forth between managed code (JScript.Net) and unmanaged code (IE's DOM) would be expensive, though, so it's not as much of a slam dunk as it might seem. - http://www.microsoft.com/windowsxp/expertzone/chats/transcripts/08_1016_ez_ie8.mspx http://www.microsoft.com/windowsxp/expertzone/chats/transcri... By the way, once a month you can join one of those chats and ask the IE developers any question you want.