This item is the same chainsaw that normally sells for about $99 (sometimes a bit less when on sale) but does not include the battery or charger. If you have other B&D 18v tools, you probably already have a few batteries and chargers, so you can save a few bucks by just buying the bare tool. If, however, you don't have any 18v tools or just one or two, you're probably better off bying the full package since this item really goes through batteries quick!
It works well, is very easy to handle, and perfect for small jobs where a gas powered machine is just overkill. Unlike an electric you don't have to deal with an extension cord. The downside is power and work time. While great for pruning, you wouldn't want to tackle a decent size tree with this. Also, you'll want to keep a spare battery or two handy since you'll get about 10min cutting time before the battery runs out.
I have several 18v B&D cordless products -- their hedge trimmer, pole trimmer, pole washer, blower, and several hand tools. All the 18v batteries are interchangeable, making it very cost effective. While not built to stand up to contractor-style use, they are more than adequate for general homeowner use. Nice design, easy to use, and inexpensive -- can't beat that combo!