First of all this post is dedicated to Make Money Online Tips as he was the person who asked the above question. This question was asked by him in response to the post “Shoot out your Questionsâ€. I have dedicated this post to him as he was the only person to comment on that post. I will give some love by linking to his Blog and Twitter @motorbeam.
OK coming to the main point, first all before answering this question let us have a look at definition of Permalinks. Permalinks is the short form of Permanent Links. Permalinks are the permanent URL of any page. The word Permalinks is mostly used in the context of Blogs. SEO for Permalinks is very important for a blog.

Now time to answer the above question. The length of Permalinks has mostly nothing to do with SEO. So the above question becomes invalid. The correct question should be “What is the best Permalinks for SEO?†First of all you should clearly understand the relation between SEO and Permalinks. Lets us refer Permalinks as URL foe time being. Search Engine spiders or bots are programmed to compare the URL to the content of the page. What bots search for in the URL are the words which are also in content. They mostly compare the URL with title of the page. If the URL contains some or all of the words of title it is well received by Search Engines. They consider it correct and valid content and rank it better than URLs which do not match with their title of the page.
So we conclude that for best SEO Permalinks should match with title. Now most of the well optimised blog has Permalinks matching the titles, so all have equal advantage in SEO. To get the edge over other, the most important SEO of Permalinks will be using the correct structure.
Below are examples of structures of Permalinks bad for SEO
1. http://greatestreviews.net/?p=123
2. http://greatestreviews.net/archives/123
3. http://greatestreviews.net/2009/03/05/nkjafabhfbjkfha
4. http://greatestreviews.net/hjsayfgafhakyh
Below is an example of structures of Permalinks good for SEO.
5. http://greatestreviews.net/shoot-out-your-questions/
Example of structure of Permalinks best for SEO
6. http://greatestreviews.net/question-answer/shoot-out-your-questions/
7. http://greatestreviews.net/post/question-answer/shoot-out-your-questions/
I consider the structure 6 the best for the regular posts as it is both best for SEO and visitors friendly. It is visitor friendly as it provides visitor with important information the category of the post.
Conclusion: Best Permalinks for SEO are those which are well structured, constructed from the words of title of the page and do not contain unwanted characteristics.

{ 12 comments… read them below or add one }
I use sitename/article name type. I read this is the most SEO friendly method as of now.
TechZoomIn’s last blog post..Kumo: Yet an Another Search Engine From Microsoft
Personally I think that having the keyword in the url twice, is better then having it once – SEO wise of course.Thus I would rather have something like:
logo/logo-designsThan something like:
/logo-designsThe second may be easier for type in traffic, however the second is better for SEO purposes.Nice post
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Yup its a nice structure. Good if you do not want to include diversions for Search Engines. In your structure Search Bot will only take the Keywords of Article Name only.But from what I have read (tested), structure no. 6 is best both for SEO and visitors.
Repeating the keyword is a good idea but not so easy to implement. It is easy only if you blog about any specific subject. For example if you do designing only post you can surely use the word designing in you Permalink.
Hey thanks alot Agent for the link love, very much appreciated. I am glad you took out the time and efforts in answering my query. I asked this question because permalinks sometimes get very big, sometimes that you cant tweet them as they are around 120 characters or so, so if you write a description, you cant add the link to the article.
I think you are using the permalink structure of category and title. I guess thats the best pemalink structure.
Make Money Online’s last blog post..How To Get Top Ranking In Google
Cool post. I agree, the length of the permalink doesn’t really matter. The content does, however. You explained it pretty well, I can’t say much more.
Austin’s last blog post..Be Patient
Thanks for complement. I look forward to more of your comments on my Blog.
Great Post! I used %postid%/%title% as my permalink as of now. But I guess this category is more seo friendly that the one I’m currently using. Thanks for this.
Millionaire Acts’s last blog post..Lucio Tan Success Story
http://www.techfreakstuff.com/2008/11/search-optimized-blogger-post-url.html Just check out this post for more information in creating SEO post-URLs for BlogSpot[a.k.a Blogger] blogs
Checked it out. Nice tip.
I think the length of permalink isn’t a factor to consider. The use of keyword(s) is. The best combination is one with keywords yet still remains readable by human.
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i am using sitename/post as link structure and its working good in seo
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