The difference is that it's perfectly reasonable to prompt your users to install Chrome Frame. After all, it's just a browser plugin like Flash. It's a very valid solution, whereas installing a VM, for most people, is not.

I actually tried for hours and hours to get this working natively in IE with VML (which is what excanvas uses behind the scenes). Unfortunately, it is just WAY too slow (each pixel becomes an "object" in VML space -- yeech). So I had to cheat with Chrome Frame for now. I am looking at implementing this in Flash for IE 6/7/8 (should be totally possible with their high performance BitmapData and ByteArray objects in ActionScript 3).

Only... Google Frame would take my grandma a second to install, and you don't need an additional license.

It's also the best the author could do without wasting hours (days?) of his life only to support a broken browser that is probably not even very widely used in his target audience.

Personally I'd have preferred a blunt "This page does not work in MSIE", but I understand that's still a risky thing to do, despite the market share figures having improved somewhat.

> It's like saying, "This software is Mac compatible!... inside a VMware instance running windows XP"

Hey, that sounds like FlashDevelop, which actually claims to be "Mac OSX/Linux compatible using virtualization software (VirtualBox, VMWare, Parallels)"