I couldn't tell from the page if it just won't boot to BSD because there is some incompatibility, or if IBM actually took steps to block BSD and other unsupported OS's from booting.

According to Pat, the problem is a BIOS bug in the affected laptops in booting with the specific partition type that BSD uses. Since FreeBSD is an "unsupported operating system" they refuse to make such a simple fix. Very disappointing indeed.