Elaborating on my comment that it wasn't plagiarism, though it would be copyright infringement.
4th edition isn't licensed under the Open Gaming License (OGL) nor considered Open Gaming Content. Instead, 4th edition makes use of the OGL's significantly less-cool cousin, the Game System Liscence (GSL).
Both the OGL and the GSL have System Reference Documents, but the GSL FAQ site explicitly states...
The SRD is a reference document detailing Terms, Tables and Templates that are
available for license under the GSL. It is a reference document and not a reprinting of the
It then continues to state...
None of the 4th Edition Dungeons & Dragons product line is considered Open Game
Content made available to third parties through the Open Gaming License (OGL).
Certain content from 4th Edition is available royalty-free for specified uses subject to the
So while 4th edition has an SRD, unlike 3.5th edition, the 4th edition SRD only contains a list of terms which may only be referenced, as opposed to content which can be used, modified and distributed.
If they had cited the PHP3.5, what was posted could be passed off as OGL and consequently reproducible, but reproducing rules from a 4th edition rulebook is a no-no.
There is a Fan Site Kit but it's just a bunch of pictures (cover art and stuff) which one can post on a web site. (Big whoop; thanks a lot WotC :P)
Other instances (such as the tables I copied from some rulebooks while answering Beyond Hit Points: Injury in DnD) are - as I understand it - acceptable; the first table was from Mutants and Masterminds - OGL - and the second was an optional side panel, from an out-of-print book, for a product which Wizards no longer has the license to sell... which I feel falls within Bryant's definition of Fair Use ;)
But I'm not a lawyer... so don't take my word for it ;)
So Bryant pointed out some interesting points about conflicts about the OGL and the Creative Commons license... I don't fully understand those.
He also brought up the fact that OGL content has to include the OGL legal-jargon. However, in the OGL FAQ It states...
Q: I want to create a website that contains many different pages with Open Game Content. Do I have to include a copy of the License on every page?
A: It will be sufficient to include a link on every page containing Open Game Content to one centralized copy of the License.
... so CC versus OGL aside, linking to the OGL would be enough, were it not for incompatibility between the OGL and CC licenses.