It is a good practice to TRY and be the first to comment. The reason for this is every time someone visits that blog post or that Forum thread will see your comment or reply.
This can drive massive traffic to your blog if you’re consistent!
However, you should not concern yourself with having to be first. You can be the first to comment or reply. Or, you can be the first to reply to someone’s comment.
The point is you don’t have to get hung up searching for blogs to comment on where you are first. You don’t have to worry if someone is answer the question first. Simply join the conversation.
I write about the myth of having to be first to cal to comment on a blog post or reply to a forum post.