is there a chance this could happen again in the future?
Any site at anytime, sadly unavoidable... Most exploits like this that allow rogue code to be injected into a site are known by the 'hackers' for weeks if not months before they are released to the public or discovered and patched by software companies... Even with perfectly up to date software today someone could likely discover a new hole tomorrow (or already knows one) and can execute the exploit against a site and there isn't anything you can do to prevent it...
Think of it this way, can you protect your house and property 24/7 from burglaries or damage? You can certainly try but realistically there is no way to avoid those determined to do the deed... You can take precautions and make it harder but in reality you likely can't stop them 100% of the time...
my browser and firewall didnt catch this thing a all before it was able to install..
Sadly that is probably because you authorized it to install unannounced to you...
I never saw the actual exploit but if it's the one Art said it was Total Security aka Total Antivirus aka Antivirus 2009 aka about 20 other names...
What this exploit usually does is pop-up a FAKE screen pretending to be Windows built in antivirus software, it does a FAKE scan of your system, but the trick is in the buttons, what is that saying about beauty is only skin deep? Same applies here, no matter what button you press to cancel the pop-up and close the fake scanner their appearance and function is only skin deep ALL the buttons are actually "Yes Please Install" underneath...
Once you gave it permission to install the rest is history, it will again pretend to be an anitvirus and pretend to be doing you good, and then it asked for payment to fix your problem... Send the extortion money to the sadly 'legit' company and it gives you back your computer or in some twisted logic fixes the virus that is holding your computer hostage ironically the virus doing harm being itself...
Also again without knowing exactly what malware was installed it might have been a lapse of you updating your software on your computer... If your copy of Windows or say your Java engine was not up to date, it could very well use a 2nd exploit that you have failed to patch to install itself...
And last but not least this program is not a virus, it's malware that results in a nuisance not really a 'threat' thus many antivirus and firewall programs will simply ignore it as it doesn't fall withing their criteria of dangerous anymore then say one of the 1001 Toolbar add-ons people install everyday...