If the placement makes sense within the world of the writing, then do so. Don't just throw in mentions of current fads or your work will quickly become dated or unintelligible to your audience. Additionally, if your book is going to have an international readership, will they understand what you mean when you use a brand that is local or national? International advertising means that most everyone knows what you're talking about when your character goes into Starbucks or grabs a Coca-Cola. They might not have the same comprehension when you have the character play Pong or drink a Barq's.