Welcome to the Q&A Forum

Funny enough I was just reading a recent article on forbes on this topic.  You can check it out here: http://blogs.forbes.com/marketshare/2011/01/23/why-the-news-release-is-worthless-in-todays-social-media-age/

I think that having a solid social network and using places like HARO, you are going to get a much better response for the effort you put in.  I think some of the cases where this can still be effective is when you have a really good newsworthy story (not a sales pitch) and an exceptional title that will not be jumped past by potential publishers.

As for a company to go to for pr's I have used prweb with good results in the past, but rarely use them anymore as we find HARO, MyBlogGuest, and building strong social networks to be far better performers.

Sorry for the delay in response, I didn't notice this until now.  Anyway, I think yolu are referring to Zemanta and Rand talked about it here: http://www.seomoz.org/blog/4-valuable-link-building-services

There could be a number of reasons.  Perhaps Google has reset the PR because of a transfer of ownership or they found the site practicing shady link tactics and removed their PR. Then again it could be that they have established a lot of quality links since the last Google PR update which mozRank is finding but Google is not yet showing.

Without knowing more details it will be hard to give a precise answer, but keep in mind even what is shown in Google PR toolbar or other pr checking tools are just a snapshot at some point in time taken prior to the last update, so it is out of date and really shouldn't be bothered with.  Unless, of course, you are concerned with the buying and selling of links, which is a practice frowned upon by Google.

It will take time, but you can help it along by using the url removal tool in Google Webmaster Tools.  https://www.google.com/webmasters/tools/removals

As has been stated it doesn't matter which one you choose, but since you do have links to both, I would pick the one with the better link profile. The one with the most or better quality links would be my choice.