Include Cross Domain Canonical URL's in Sitemap - Yes or No?

[WEB-IRS]

I have several sites that have cross domain canonical tags setup on similar pages.  I am unsure if these pages that are canonicalized to a different domain should be included in the sitemap.  My first thought is no, because I should only include pages in the sitemap that I want indexed.

On the other hand, if I include ALL pages on my site in the sitemap, once Google gets to a page that has a cross domain canonical tag, I'm assuming it will just note that and determine if the canonicalized page is the better version.  I have yet to see any errors in GWT about this.   I have seen errors where I included a 301 redirect in my sitemap file.  I suspect its ok, but to me, it seems that Google would rather not find these URL's in a sitemap, have to crawl them time and time again to determine if they are the best page, even though I'm indicating that this page has a similar page that I'd rather have indexed.

[MoosaHemani]

There is no BIG problem if you add the pages that contain cross domain canonical tag on them. Why?

The reason why I can say this is because Google is not only indexing the pages from sitemap.xml file, Google have their own crawler and they have the ability to crawl and index the website no matter if you do not have an xml sitemap.

Google is very good at (in my opinion) picking the instructions that are available on the page so if you add the page in the xml sitemap, the crawler will read the instructions on the page and will only index the page that contain original content.

[AgentsofValue]

Right - as far as I know, you're supposed to put end URLs into a sitemap, not urls which 301 redirect.  Cross domain canonical is still kind of new, but I would treat them as a 301 redirect and not include them in a sitemap.

Now, if you're curious, SEO Moz did a whiteboard Friday where they talked about this same exact issue (cross domain canonical), and as an experiment, re-posted a blog article from another blogger on SEO Moz.

http://www.seomoz.org/blog/cross-domain-canonical-the-new-301-whiteboard-friday

http://www.seomoz.org/blog-sitemap.xml

http://www.seomoz.org/blog/the-story-of-seomoz

The blog is still included in the blog sitemap.  I think it probably won't 'hurt' to keep those pages in the sitemap, since a lot of sitemaps automatically generated CMS tools won't have been updated to deal with this yet.

[WEB-IRS]

I looked at the sitemap, and they are including the http://www.seomoz.org/blog/the-story-of-seomoz but not the canonical page - http://www.masternewmedia.org/entrepreneurship-the-full-story-of-seomoz-told-by-rand-fishkin/

So based on this example, the page on SEOMoz is still included in the sitemap, regardless if it has a canonical or not.

This seems to make sense, since canonical links are used only as a hint and not an absolute directive.

I also noticed that Google is choosing to index and rank both pages, on Page 1.

SEOMoz  is ranking higher on my browser for "the full story of seomoz".  A few things going on here.

1. Why is google choosing to rank SEOMoz higher than Mastermedia.org for this page?  There's a canonical setup, but google is choosing not to follow it.  (again its a hint not an absolute)  this doesn't always work.

2. I would think Google would be able to filter out the duplicate content easy.  In this example, they are clearly not.   SEOMoz is ranking #4 and Masternewmedia.org is ranking #5 for query "the full story of seomoz"