Office 2010 is definitely a great improvement from previous versions of Office. One of the features I have liked is the ability to insert videos and audio from websites like YouTube in a presentation (hacks for video insertion in previous office versions).
However, certain versions of PowerPoint 2010 grey out the option to insert videos and only allow you to insert videos from a file. The problem is that inserting videos from websites is not available in 64-bit versions of Office 2010 or PowerPoint 2010 due to it requiring a 64-bit Adobe Flash installation.
The same feature is available on a 32-bit installation. So if you are using a 64-bit version of Office or PowerPoint 2010 you will be unable to insert videos into your presentation from sites like YouTube.
Is there a workaround? Yes, there are couple of workarounds. First of all you could grab yourself a 64-bit version of Adobe Flash from Adobe Labs and install it to solve your problem. The 64-bit active-x for Internet Explorer worked for me. However, you must note that the 64-bit version of Adobe Flash is in beta stage and may result in frequent browser crashes, though I haven’t seen any yet.
Another alternative will involve a lot more work than simply using the feature itself. To insert videos in your presentation. You will first have to download the videos to your desktop (resources for downloading videos from internet to your desktop) and then insert it as a file into your presentation.
Hopefully, the Adobe Flash 64-bit player will be available to public in near future, thus solving a problem with inserting web videos in PowerPoint presentations.