There should be a manual with it, but if it can browse, it has software... and if so, it might be vulnerable, but I've never heard about anything like that. I wonder if it works with flash memory or uses a HDD - again, your manual should tell you.
I think your questions are valid, Philly and would advise you to find out from Samsung. Also, since your TV can use apps, check the security testing in the Samsung App Store - do they have rigorous requirements for their apps? Do they test them?
I only ask because you'll probably end up hooking various AV devices up to it. Also, what OS does it use? Do you plan to do taxes/purchasing online? That's what would make me think twice about it.
If your TV runs a different OS from your 'puter, the likelihood of cross infection is likely zero.
Very good questions, though.