Adding the new note board to your pagelayouts seems like a nice way to allow comments on newsitems and provide a some more social element within your site, however in terms of configuration, you don't want to have to add the note board to each page you created, and add it to a pagelayout. So I created some pagelayouts and wanted to add the note board WebPart to it using its xml, therefore I exported the Note Board WebPart, however when putting it back on the page it gave me an error, so once exported it can not be imported again.
If you want to add the WebPart to your pagelayout you can use the following xml to do so (it is taken from the MySiteHost Site Defintion, and works as a charm):
1: <WebPart xmlns="http://schemas.microsoft.com/WebPart/v2">
2: <Assembly>Microsoft.SharePoint.Portal, Version=14.0.0.0,
3: Culture=neutral, PublicKeyToken=71e9bce111e9429c</Assembly>
4: <TypeName>Microsoft.SharePoint.Portal.WebControls.
5: SocialCommentWebPart</TypeName>
6: <Title>Note board</Title>
7: <Description>Description</Description>
8: <PartOrder>3</PartOrder>
9: <FrameType>TitleBarOnly</FrameType>
10: <AllowMinimize>true</AllowMinimize>
11: <AllowRemove>false</AllowRemove>
12: <IsVisible>true</IsVisible>
13: </WebPart>