In a situation with former employees, you have to take into account all that has happened with them. Because the employee sure will (for better or worse).
If you have different groups operating for hiring, they need tools and info to work better. I'm not faulting google for this incident, I just think it could be done better.
So that they don't write blog posts like the one we are commenting on? So they don't actively try to convince other (possibly talented) potential employees to ignore your recruiting efforts?
The entire comments section here seems to be "is Google a horrible company to work for and does Google+ suck, or are they merely ok?" If you're looking for new talent, wouldn't you rather have prospective employees asking "is Google a fantastic company to work for or an outstanding company to work for?"
The only thing on the line is reputation and people don't like to be "spammed" unless they ask for it.