Users are free to configure their systems for higher security. Note that doing so may limit functionality you are used to. For example, you can configure your system so that all users run as normal users (no administrative functionality). Running users as normal users is part of all security guidance. Not all XP software will run if you do this. You can set IE to high security mode by default and disable Flash, etc. Doing so breaks much of the web but is more secure. You can get security, but it will impact your user experience.
It is easier to secure Vista and 2K8 server systems.
We have no evidence for black holes of less than multiples of the sun's mass and to the best of my knowledge, no evidence of black holes of masses on the order of many billions of solar masses. The rest is speculation, but not unreasonable.
There was a very interesting paper at the LANL archives last year on the energy release from small black holes on planetary bodies due to eddington-limited accretion. The impact would be correspondingly greater and more observable in white dwarfs and neutron stars.
If such stable black holes were creatable / existed, we should see rather remarkable things with old white dwarfs and neutron stars, which would be greatly affected by such energy sources.
Strong passwords / keys for WPA is not much of a burden. You only have to enter the damm things once. I use a random 32 character hex string as my key. I wrote it down and stored it in a known location. I also have it stored in an old USB drive in a text file. I have to enter it far more than most people, as I dogfood WIndows releases, flattening my notebook each time. Thus I have to reinitialize it for my home WPA network each time I rebuild it. I am not worrying about brute force attacks against 128 bit key values.
Actually, it is rather more like the Zotob vuln than the Blaster vuln. It is a crit on earlier systems, but requires authenticated privledges on Vista and 2K8 server due to the implementation of the integrity level defenses in Vista and 2K8. That said, the potential for damage with this vulnerability is high and there were reports of attacks in the wild. Thus, Microsoft released out of the standard release cycle.