Get a wordpress.org url (your site will be "yoursitename.com). After this, install a Thesis theme. This will open a lot of windows for you in terms of SEO plugins, plugins in general and it will expand the overall capabilities of your blog. Look in to SEO tricks and tips. Also, you will read a lot of advice directing you to comment on other blogs or to become more social with other authors to increase traffic via interacting on the blogcatalog forum. Don't even waste your time with this. The only traffic you will receive from this will be from other bloggers (not their readers) and the only reason those other bloggers will go to your site to begin with will be to reciprocate your comment(s) if you left one and to make themselves known to your own readers. And when it comes to blogcatalog forums....shit... If you've been an avid poster/reader of CP, trying to interact with that community feels like interrupting a tea party by walking into the dining room naked, climbing on their table, bending over, spreading your butt cheeks, shitting into their tea pot and walking out of the room while the other people in attendance remain deadly silent with an exception of the "positivity in everything" aphorism guy who blurts out a 1-liner, trying to make sense of this newcomer in ultra-positive fashion. It's so ****ing lame.
All in all, focus on this: SEO, useful plugins, the appropriate theme/server for your niche (I prefer wordpress.org, not .com) and most importantly, quality material that will connect with your target audience.
If you want to be taken seriously, stay away from blogspot...things get real gimmicky, real quickly there...plus, as of the past 6 months to a year, blogspot/blogger has been dying at a rather rapid rate. Blogspot.com bloggers these days, generally consist of your comment/comment-reciprocation whores. You get no "real" traffic there...just traffic that consists of other bloggers who may read/view a small fraction of what you post.