As far as Turbine goes they are usually very very careful about these things. My main gameplay atm is from Turbine's Lord of the Rings Online (played since closed beta) and have never never never had an issue with hacks since Turbine began long long ago with Asheron's Call (which I played for 10 years).
Turbine being down for maint is nothing to be alarmed about...Forum and game maint are very common and very often. In fact, Turbine is one of the best out there about system maint and monitoring for all those shady things. If something does go wrong, and it has in the past, they are extremely vigilant about getting things fixed and back online. I've witnessed their techs work around the clock for days until it's right. They are also REALLY REALLY good about compensating their players if something negative does occur.
A lot of the other game companies out there *cough* could take a big example of that....
From the mighty mixed drink -- Jackncola