Question: So far any search for Pogoplug security risk does not bring up anything alarming. Just wondering if anyone else has run across any mention of security issues with this device.

Answer: 
The pogoplug essentially makes a connection to the manufacturer's server and provides content through it, at least in part. In my book that is a security concern, but for most people it is no more a threat than posting your pictures on facebook and only letting your friends see them is. 

You're trusting the manufacturer to actively protect your data though, rather than passively protect it by designing a good password authentication scheme (for example).

This is based on what I've read about pogoplug which is very little recently, and a bit more, but a lot longer ago.
Nope!

I have been hearing a lot about this device recently in the trade press and I haven't seen anything about security.

That being said, no one can say any product is 100% secure, and the company does appear to be around for the long term, so I am sure they will patch any problems.