Rhea posted a detailed review of SEO audit tools comparing tools from Web CEO, Alexa Site Audit, Website Grader, Website Auditor and SEOmoz Tools. There is also a recent article at Search Engine Watch on SEO audits and tools you can use to help.
The Sphinn thread on the topic has comments from Jill Whalen & Incredible Help asking why would SEOs use these tools? One asked, "why would we as SEO's give credence to such tools?"
There's a world outside of SEO agencies/consultants. In-house SEOs use tools like this all of the time. Do we? No, but we wanted to audit our process more than the tools themselves. It's competitive research and we had a couple of new ideas as a result. This makes us and our tools better and as we mentioned in the post, none of these tools can replace the experienced eye of a SEO. At the same time, we can't take on everyone that contacts us, so for the more technical leads that just need to cleanup specific things, these tools can helpful and if they free them up to focus their budget on other areas like link development, content creation or social media, I think that's great.
My question to you is do you use SEO audit tools? Take my poll:
Forum discussion at Sphinn.