If you keep up with the latest news on SEO and link building methods. A lot of talk has been going around from the web spam team leader Matt Cutts and has caused people to be weary of guest blogging for personal improvements of their websites. A lot of people have utilized guest blogging over the years as a good form of getting new readers and also the SEO benefit of having link juice from an authority blog.
As like any method webmasters are always adjusting to changes made by Google and adapting to what now works for SEO and getting links for their site. First it was plain old link farms back in the day, then web directories, then article marketing, blog networks and now guest blogging. Google is making it harder than ever to use free methods to rank up your website.
You can see what Matt had to say back in January about guest blogging at that link.
Now the big question is how can google determine what is a quality guest blog post and one that is purely done for the benefit of the guest blogger looking for link value? I understand Google wanted to keep quality of search engine results the best for the browser. Keep in mind guest blogging is usually valuable to both parties, for one the guest blogger does want some compensation for taking the time to write a quality article and posting it on another blog besides their own... Then of course the blog owner is receiving the benefit of getting a quality post published on their blog which will help their readers.
So remember when utilizing guest blogging always try to focus on quality. If you are spending 15 minutes to write a quick article for guest blogging most likely it is not a high quality post that is likely to be published as a guest post. Many people are also taking advantage of paying for placements as guest post. Keep in mind generally if you have to pay money for a guest post it might mean that your purpose of wanting to guest post is purely commercial and just for the link value. I know there are services that offer guest posting such as Nationsubmit SEO but as long as their content is high quality and providing something to the readers it should be okay.
Another thing to keep in mind is where is the link going that is to be used in the guest post? Ideally I think most blog owners that allow posts on their blogs want you to link to your own blog or any other non commercial link. As I mentioned earlier linking to a commercial site will either be rejected or asked for an inclusion fee which Matt Cutts does not suggest doing.
I do not think though overall guest blogging has been ruined but of course Matt Cutts does have to put this out there to control quality of posts and giving what is really helping the readers. If there is no control over these things we would end up with a internet full of spammy blog posts offering no real value and taking up space.