Is there a difference between researching keywords for blogs and researching them for traditonal websites?
Yes and no.
You can treat blogs the same as traditional websites and do keyword research for each and every post you make. In fact, I am sure that some pro bloggers do this. However, it is my opinion that you don’t need to do this. I think that for some percentage of your posts you should forget about keywords and just post whatever you want to, without any regards to Search Engine traffic.
Why do I recommend this?
1. You will likely rank high for some long-tail keyword that nobody else does.
2. By not focusing on generating Search Engine traffic you will be able to focus on writing good, quality content. Which in turn will bring in links to your blog. Which brings traffic to your site.
3. Not worrying about keywords can make blogging more fun.
That said, it is still best to do some keyword research for your blog AND to focus on writing good quality content.