There’s no question PR (and online distribution of news releases in particular) is beneficial to search engine rankings. Links are SEO fuel and well-crafted and placed news releases can provide text-specific links from high-authority news sites.  While there is some debate about how recent changes to search engine algorithms may have affected the value of these links, there is no question that they remain important. So which online press release distribution sites are best for SEO purposes?

Before answering that, a quick review of a few PR+SEO best practices:

• • Write high-quality, “newsworthy” news releases. Never write news releases only for SEO purposes. High-quality releases are more likely to catch the attention of your market, get picked up by high-authority news outlets, enhance your brand image and provide valuable backlinks than keyword-stuffed fluff.
• • Include text links within releases. In this press release for example, notice how the phrase records management software points back to a highly relevant web page for that term. This may seem obvious, but never use a press release distribution service that strips out these links. There are plenty of alternatives that will leave your links intact.
• • Use at least one paid service. While it doesn’t hurt to use free services as well, journalists tend to pay more attention to news releases from trusted, paid sources than to the free ones and paid services generally provide better placement.

Okay, so which sites are best? Answers vary depending on who you ask.

In How to Select the Best Wire Service to Distribute Your News Release, Robert Beadle places PRWeb and PR Newswire (following upgrades to its website) at the top of his list for most organizations. He notes that Business Wire is also very strong, but is the most expensive of the “big four,” is most suitable for large, publicly-traded companies and the PR firms who serve them. He places MarketWire at the bottom of his list, though it is reasonably priced and has strong distribution for more localized and IT-related news releases.

Ted Weismann, in What Do You Know About Your Wire Service’s SEO Practices?, notes that PR Newswire initially took a search traffic hit from Google’s Panda update, but has since made changes to its site to regain lost ground. Business Wire has also addressed Panda. It’s not clear what other PR distribution sites have done to respond.

Search guru Lee Odden, in the SlideShare presention SEO + PR Tactics and Measurement (which also contains some excellent general guidance on optimizing news releases for SEO benefit), favors PR Newswire, though he notes that all of the big four provide SEO value. UPDATE: Lee actually endorses PRWeb for SEO. See the comments below.

This Press Release Wire Service Comparison from Clarity Quest ranks PR Web on top, and echoes Robert Beadle’s conclusion that MarketWire is a viable alternative for budget-conscious local firms. Unlike Beadle, however, the team at Clarity Quest doesn’t view Business Wire as an expensive, big-company-only alternative, stating that “Through their partnership with PR Web, you can get one of the best deals on the Web…For smaller B2B companies and startups, we use the BusinessWire package with PR Web.” The post goes hard on PR Newswire, but it’s not clear if this opinion reflects the recent changes PR Newswire has made to address SEO issues.

Based on traffic trends from both ComScore and Experian, PR Newswire leads all of the service in search engine referral traffic, followed closely by PRWeb, then in order Business Wire and MarketWire. Globe Newswire comes in the bottom of both graphs.

So much for the experts. What do actual PR practitioners think? According to this LinkedIn discussion on What is the best Press Release Service for results? Free or Paid, PRWeb (owned by PR monitoring firm Vocus) is the clear winner, followed by PR Newswire. Business Wire and MarketWire get honorable mentions, as do a few other lesser-known fee-based and some free PR distribution sites.

The bottom line? All of the big four do a pretty good job at helping with news release links for SEO. Which is the “best” service depends on your particular situation. PRWeb seems worth checking out for almost any company, and is a no-brainer for those already using Vocus. PR Newswire is another strong service, though slightly more expensive. Business Wire is likely the best choice for large firms with correspondingly large PR budgets, though its package with PRWeb is worth investigating for smaller B2B vendors as well. MarketWire appears best for budget-conscious companies and those primarily concerned with local news release distribution (and is also effective at reaching targeted industry publications).

Have a different opinion, experience or perspective? Comments are welcome.