Lets just run this through a thought experiment, shall we?
There seems to be no advantage to hacking Finney's account, unless there were some personal messages that contain some private information.
No one is going to take a post from the now-passed Finney as legitimate or credible.
Bitcointalk's security has been penetrated many times, so it may just be simple curiosity on the hackers behalf.
In any case, it doesn't seem like there's much to be gained by controlling a dead man's account - unless Hal used it (highly doubtful) as part of a two-factor scheme for something more valuable.
It could be someone probing to see if Finney's personal messages contains any clues to the identity of Satoshi. We all know how much bitcoins
are being held by Satoshi, and this will be the ultimate treasure hunt for them. There are people out there {grave diggers} ...who will not think
twice about digging into Finney's private messages to get to Satoshi's coins. I respect the dead, and will not disrespect him, by doing that.