More work than most people realize but can be rewarding in the long-term if you stick with it and have quality content.
Blogging can be fun, when you have something that you are interested in. Do some good quality reviews and good back links and seo. If you are a really good at reviews, you will do well and get the traffic. You have to have the staying power also.
No it is definitely not a waste of time, but if you are expecting overnight results then don't bother. It is important to choose a specific niche that people are interested in, but is not saturated. Don't create a blog on a broad topic like shoes, go for something like German hiking boots (long tailed keyword that is very specific). It will help a lot if you are also interested in the topic, but the most important thing is to do your keyword research to see if there is a market first. Create loads of great content and interact with your readers. But most important of all, be consistent with your posting and be patient. Most people give up after 3 months because it appears like nothing is happening. Just like a plant though, it takes time to break through the soil and for the results to be visible.
ya really it is worth the time, with doing proper seo you can gain traffic and earn some cash by putting adsense on your blog.