I would agree with Alex, there is a huge difference between enjoying playing games and watching film / tv to working on them. All of those industries are very high pressure wotking environments, and whilst they are often very rewarding, people can get very disheartened when they realise that making games isnt always as easy and fun as playing them.
That said, only you can really answer that question. If you want to do it as a career then make sure you work hard at it, its a competitive industry.
And yes, game cinematics do use a lot of matte painting, see www.thunig.com