I know, the answer is rather simple to this. Blogs do indeed drive traffic. Would adding one to one's company help increase the flow of new customers? Honestly, I think it would as long as useful information is given. It would also help build a search engine ranking, in my opinion, since search engines love new content. Does anyone have any experience with this or had this in their mind as well?

I agree that blog will drive traffic.. It's also a source of information for visitors if the blog's topics are based on your company.

This is true. I am implementing a blog along with some other helpful information in our new update that we are currently working on. It's a lot of work to do as much as we want to do, but, it is worth it to give something else that is helpful for our clients. A blog will also show how professional the person that adds to it is.

Well blogs "can" drive traffic. It's not necessarily a "definate" thing.

It truly depends on the content of the blog.

Is it informative? Is it funny (doesn't have to be. Just an example)? Basically, does it contain content that will make me want to come back and read it again?

Blogs are just like any other web site or web page. If the content is pointless, useless, or boring....no one is going to want to continue to come back over time.

Well, no doubt blogs increase the traffic, but what percent of this traffic turns into clients? Is there any formula for this?
And can we use the forum on the site to increase the traffic?

Anything can help lead new clients. It is all about how you are presenting information. Do you have anything related to webmasters that will draw them to your forum? Being seen seems to be one of the best things a company can have, unless you're presenting your company image in a bad way. If you're seen and people know of you, it can produce the potential for new clients. Reputation is everything.

Having quality content is the key to getting your blog traffic. Sites like digg and delicious can be a great way to drive traffic as well if done right.

Also leaving sincere comments to another blogs help to generate backlinks and traffic.