You have Maurice Blackburn and Slater and Gordon who do class...

You have Maurice Blackburn and Slater and Gordon who do class actions on behalf of shareholders all the time. I have been involved in a couple of these, namely:
Babcock and Brown
Dick Smith

Sadly never saw anything out of them though. However those 2 were not as clear cut as what IGE is. With IGE you have undeniable evidence that the directors have not done their due diligence and provided misleading statements to the ASX. Whether knowingly or not, is what the courts and evidence needs to prove. I find this case is easier to prove than the other 2 I mentioned. Those had more grey areas. IGE seems that bit clearer on what has occurred. Two statements in one day come out stating funding is secured, while a director is selling shares. Even a half decent lawyer can grab this and run with it.

Directors are not as immune from liability as once thought. If found to have breached their director duties under the corps act, they are personally liable. If shareholders get nothing, I suppose the bittersweet outcome will be that the directors were held personally liable and suffered financial loss as a result