I've been asked many times what's the difference between the two. I suppose it's a consequence of structuring these as module blogs. If we look at blogs through that lens, then yes, blogs are similar to forums in many respects.
But I want you to look at blogs from a different angle today. Think of blogs as websites.
Which is what they are, of course!
But as websites, blogs are much better because:
1. You don't have to deal with code.
Yes, everything in blogs are templated. You fill in a text field to create content. No more dealing with HTML (unless you want to). Even if you have to edit HTML, it's mostly to copy-and-paste code for things like YouTube videos and the like.
2. Your content gets archived automatically.
Since blogs are presented in reverse chronological order, content is time sensitive: the most pertinent thing is displayed on top. The older posts go further down the page and eventually go off the front page. But it's still on the blog as every post is automatically archived. You can find them later through: (a) browsing the categories (if you have categorised the posts), (b) going through the monthly archive or (c) my favourite way: the search field on the blog. You don't need to worry about moving stuff from your website.
3. You can change the website's design without affecting the content.
In blogs, the form is separate from content. You can change the look of the blog without touching the content. Try doing that with a normal website; even with templates, it's not easy.
4. You can also create static information pages, just like a website.
First off, I have to admit that Community Server does a bad job with pages. Most of the templates make no provision for the display of the links to these pages. For example, the Using Module Blogs FAQ is a page, not a post. It never appeared on the front page of the blog. However, the link never appeared anywhere on the blog either, so I've had to manually add the link in the sidebar.
That being said, creating a page is dirt simple. You just use 'Create a New Page' in Community Server. You'll be presented with a text field, similar to the one for creating a post. (You can even name the page, as I have done for the FAQ. Check 'Advanced Options' > Click Options tab > Type in the name in the Name textbox. Once you've created the page, grab the URL and paste in into your sidebar. (Reminder to self: Post a mini tutorial about this.) Here are detailed instructions about how to create a static page.
5. You become good friends with Google.
Search engine optimization is a complex field. Suffice to say, Google likes blogs. I suppose this is because bloggers tend to link to other bloggers' posts. Since linking is very much part of Google's search algorithm's, blogs rank highly. Also, there's usually a constant flow of related content which gets picked up by Google's spiders. Incidentally, one of my previous posts is ranked No. 1 in a Google search for Blogs v Forums. (A slight change in the search parameters changes the result though.)
6. You can be part of a worldwide, multi-disciplinary forum.
It's called: the blogosphere. Writing blogs, reading others and commenting opens up a new world. I don't know how to stress this. I've met many others with similar professional and personal interests through blogs. I sincerely hope that you will too.