Please let us know when this works, as per the channel9 video when the VS install directory is not drive C. (Boot [C] is a relatively small SSD, installs are in D, data is in E)
Mads, this looks like it would be great if it would work for me, but I've already spent a bunch of time dealing with the 'SP1 is required' issue, then seeing people reviewing about the problems with a typical, but apparently non-standard, installation location.
Since the video and hype is great, but the installation and usage has such issues, I've voted 3. It isn't crap or vaporware  and it isn't gold  (at least for me, get the installs fixed, then maybe).
Unfortunately, I had to uninstall this. After installing I could no longer edit CSS files in Visual Studio getting the same "unspecified error" that others are mentioning. Once I uninstalled, I could edit CSS files again.
Do NOT use this. After installing it, Visual Studio lost all ability to recognize CSS files, let alone have intellisense function. Uninstalling and trying to fix Visual Studio was a nightmare. Bad, bad, BAD extension.
Since there is no such thing as Web "standards", I understand that you mean W3C "Recommendations"; however, the vast majority of the technologies this update/tool supports are not recommendations yet--they are still drafts, or at best, *proposed* recommendations.
I'm completely baffled by "standards" zealots, and browser makers, who so enthusiastically start using draft specifications. You either want "standards-compliant" browsers or your don't. You can't have it both ways.
Read it and weep "standards" zealots!
Did the Wouter fix to get it installed and past the SP1 is not installed bug. Then, when I open a stylesheet, CSS3 was in the target dropdown, but it would not actually select and I would get no intellisense for CSS3. I performed a "repair" and then I would not even be able to open a css file. The first time I tried to open the css file, it would throw an error like "could not locate that ..." If I tried to open the css file again it would throw "The operation could not be completed. Unspecified error." Had to uninstall it all. :-( Running Win7 on a 32-bit machine. Windows is on drive D, VS2010 and this update are on drive H.
Unable to open a stylesheet using the CSS editor. "The operation could not be completed. Unspecified error." Debugging an instance of devenv.exe did not provide any more clues, as it never stopped on an error when opening a css file. Removed older HTML 5 intellisense updates, and re-installed VS SP1, still got error. Had to uninstall
W7 x64, system on c:, VS and this update on d:
Had the same problem, no need to reinstall, don't know why it just wasn't copying the files, so unpack msi with universal extractor go to vs dir\Common7\Packages and copy extracted schemas/css/css30.xml file from dir 1033 (or other as yours in vs) to the same dir in vs path, do this same with schemas\html replace all files and it is done, work for me.
I had used the Wouter vanEck trick below because VS2010 was installed on D:. I found that it copied the files to C:\Program Files\Microsoft Visual Studio 10.0\Common7\Packages, which makes sense because that is where it was looking for Visual Studio. I was able to copy the files from there rather than unpacking the msi.
Just wanted to point out that yesterday's Windows Updates caused the not opening CSS bug again. Settings reset didn't work but had to repair the WebStandards sw, then reset VS settings in order to get the system up and running again...
I was initially prompted to install SP1. After that, I installed the Web Standards Update successfully into the default folder (C:\Program Files\Web Tools\Web Standards Update for Visual Studio 2010 SP1\). I reopened VS2010 and even reinstalled it but it's still not working as I see no options for HTML5 or CSS3 within VS. Do I need to also do the Wouter fix? Thanks
By default the WSDL generated for a Web Service is hierarchical (and compliant), creating multiple files for a WSDL. However, older, non-Microsoft tools do not handle it well.
How about a feature to make the WSDL flat without having to implement a set of classes to force the WSDL to be flattened as discussed here: http://blogs.msdn.com/b/dotnetinterop/archive/2008/09/23/flatten-your-wsdl-with-this-custom-servicehost-for-wcf.aspx and elsewhere.