I don't think Smart TVs are worth it personally. Having the smart TV aspect of the tv adds a lot of extra cost to the TV, whereas you can get a non-smart TV (or one with very basic Smart TV) with better picture quality for less. I am not sure about the Hockey Streams. Basically you can use apps like Netflix, Facebook, etc., things you can already do with a computer or game console if you hook it up to the TV.
I would look for a deal on a Panasonic plasma as they are not making them after this year. Best picture you can get, IMO. I just got this 50 inch Panny and it's amazing: http://reviews.cnet.com/flat-panel-t...-35831110.html. It has some Smart TV aspects like Netflix and Hulu Plus if you are in the states, and it is a very good bargain for an awesome picture. If you are in the States, the bargains are a lot better and you can even get the 65 inch model for cheap.
The one I have is only available at wholesalers like Costco and Sam's Club, but the S60 series (http://reviews.cnet.com/flat-panel-t...-35558333.html) is available everywhere. Only difference is the S60 series has a worse picture in bright environments since it does not come with an anti-reflective filter. I have had/seen basically every type of TV and you just can't beat plasma IMO. For hockey it is a bit duller at first since it is not as bright as LED/LCD TVs, but it is more natural and you get used to it.
BUT it depends on what you already have. If you have a game console or a Blu Ray with its own streaming apps and web browser, then I definitely think it's not worth the extra price.