Dreal: Actually scratch that - I see the issue. Give more people 'wired' type connections to the network to do hacking (which in most cases isn't hard), like password sniffing.  

Has microsoft offered a solution to this? (Like not allowing wifi sharing on some networks) ...Surely they will....

not sure: Post here: http://www.geekzone.co.nz/forums.asp?forumid=45&topicid=181362

Giving people the ability to invite all their firends in their contactbook with one mis-slip of a finger - dumb as dumb can be.  it only takes one slip up and your internal network is breached. 

I saw a govt Dept get virused bacuase someone plugged in an MP3 device - despite a ban on all BYO items. BYOD, BYOA, allowing social media which is hardly secure, it's not good for business in either a security or productivity sense. Add to that the whole google / facebook / mozila / microsoft will keep your passwords and do authentication for you stuff and it gets worse. Eggs in one basket.