There are many threads that touch on this in passing but I haven't been able to find a set answer anywhere.

I just received my pogoplug, hooked up my harddrive and am going to share my picture folders with a few friends.  I set it up as password protected so I imagine they will get an email saying I'm sharing something with them, they will then have to create an account with a password in order to sign in and view said pictures.  

Now there is a lot of talk about sharing and this two week time limit.  What is this all about?! I couldn't figure it out for the life of me.  Does it mean...

a) they have two weeks to take action to the email or their "invite" expires.  (which makes sense... no need for an endless invite)

b) even if they create an account they only get two weeks of access to the folders before they get "locked out" and would require another invite to gain access (which seems ridiculous...)

C) Something else all together.

Please advise.  Having to reinvite them every few weeks could be a major deal breaker and more than likely result in my returning the product, which otherwise seems neat.