I have invite people to be guest bloggers and have been a guest on other blogs and love it. My blog
http://www.portraits-by-nc.com/blogs has a variety of sections and especially one dedicated to shopping, which is a great section to feature a guest blogger from Etsy.
Guest blogging utilizes the amount of readers that each blogger has. If they are savvy enough, bloggers have their blogs set up so that the content is automatically pushed to all major networking sites, plus their email subscribers. Often both the guest blogger and the owner of the blog will share the content, which means that all of a sudden the content is shared to a large number of potential clients.
Google loves links from your blog to other sites and vice versa. The additional traffic that is generated does wonders for your blog and website.
However, I have to say that just writing a blog post on someone's blog is not enough. Both parties have to share the content via FB, G+, Twitter, Pinterest, Stumble and any other site they belong to. Also don't be surprised when people do not leave comments. Most don't like to leave the network they are visiting. A person on FB will like the post and even might share, but seldomly click over to leave a blog comment. To entice people to click to the blog giveaways work best.
I am featured on a blog 2JustBYou and offered a free portrait see here
http://linkis.com/www.2justbyou.com/20/emwoC The amount of traffic it has generated to my blog and on other social networkign sites is incredible.
If you like to be featured on my blog
http://www.portraits-by-nc.com and like to offer a giveaway item, email me. You can see my blog reach stats here
http://www.portraits-by-nc.com/advertise/So should you do it? Absolutely! It's a great way to get your work seen.