After downloading and installing the MS anti-spyware app, well it does work. Of course, being a somewhat careful surfer, the only place I notice it working is in the same areas that SP2 already took care of on XP, because the laptop I loaded it on is 2000. It asked me to shut down the Messenger service, and blocked Active X controls from being downloaded without me giving permission first. Those things are already part of SP2. There are other features that SP2 doesn’t have, and the warnings are much more detailed than they are in SP2. (Assuming SP2 warns you and doesn’t just make changes without telling you like it does by shutting down the Messenger Service. And yes, I noticed that one specifically because I use that service at work!)
Overall, it’s a nice effort and it will probably get better. On the other hand, it should only be a part of your whole security plan, not the only tool, and if you’re running in a network environment, you probably want to check with your admin before making any configuration changes, like letting it shutdown the Messenger service.
Now let’s see how they market it, how many people wind up buying it if it winds up being a subscription, and how well MS does updates and defines spyware going forward. Like I said before, there’s your real test to how effective it will be.
Update: Serge has an interesting idea related to users who haven’t installed SP2 on an XP machine:
Maybe the app should suggest that they install any missing service packs too.