If the previous site had more links to the www version, stick to it. Users remember your site as www, so there's no point on fooling them now. And same happens with Google.
Also, Skweb is right, follow the advice and stick to just one version.
Now, just for those wanting to know why (as Skweb says there are a variety of reasons):
- if the majority of links go to the www version, it's going to be easier to Google and other SEs to understand it and to give proper value to those links and to those that now will be redirected.
- in any case, the average Joe is used to the www version. You may like it or not, but there's no reason to make it difficult for them (unless you do not care about visitors). Skweb says neither is superior to the other, but I slightly disagree: people is biased towards the www version and they tend to link it.
- Google treats non www and www as different websites, so you must always stick to only version. Any reason to no keep the www?
- That above said, you have to think about it and how it may affect indexing: a link to the non www version is redirected to the www version. Therefore, Google needs to follow the first non www link, store it, find that is redirected, go to the www version and then analyze it and give proper value. Making it easier (simply going to the right version) will always be better for you.
- Wordpress is quite for SEO and the choice given was right. Now choose the right one... (see above)
- This may sound redundant and probably it is, but most of the times choosing the www version or not it's a matter of personal opinion (same as above by Skweb, none is better). Given all the reasons above... will you disregard these reasons and just use a different version just because you like it?
- I know linking it's now allowed, but I believe this one falls on the allowed ones: [w3.org
]. A good URL doesn't change. Never, ever. As many you have that doesn't change, the better. And if it changes, redirect 301 to the new one.
- This is bit technical and might not be important if you do not have a lot of traffic or server resources problems. But the thing is that as more redirects you have, more server resources and bandwith is used. If ask for 20 images, CSS files, scripts or whatever to a version and I'm redirected, this means the information that is requested and sent is multiplied per 2. Why would you do that if you can avoid it as much as possible, leaving this situation just for these few links you have to the non www version. Quick example: I ask for http://example.com/image.jpg and the server says it's moved to http://www.example.com/image.jpg. Isn't better to everyone if I directly request for http://www.example.com/image.jpg ?
I know these and many more reasons have been already posted on the forums, there's nothing new in my post, but -IMHO- it's always good to remember it.
Summary: follow Skweb advice, keep only one version (the www one), stick to the most used, make it easier for both users and bots.
Just my 2 cents.