How safe is it to use Silverlight in production for a graphic form?
I don't know whether it's installed on most computers, but the number is growing. It's a small download and if it's not installed the user can install it with a single click.
This page has some graphs:
Adobe Flash is on 97% of computers.
Silverlight is on 55% of computers.
Java is on 73%
I have no idea how accurate these figures are, but they seem to be believable.
Once installed it uses Windows Update to keep itself up to date.
As Anthony states the current released version is 3. Version 4 is at Release Candidate and will probably be released within the next couple of months (as of March 2010). I originally thought that the update would happen automatically, but the RIA Stats page indicated that Silverlight 2 and even 1 were still installed on some machines so this can't be the case.