Xbox and IGN are both pretty well know things if you are into entertainment. They both use Twitter and Facebook but both post the same exact content on Twitter and Facebook. They also don't reply on either of them. However Xbox has a Xbox support twitter that does respond to you. IGN has pretty similar amount of followers/likes on both of their accounts but Xbox has over 3x as many likes on Facebook than followers on twitter.
Xbox posts seems to stick to advertising their content such as deals, and trailers. IGN posts more about TV shows, DLCs, updates, and strategies. Both post pretty frequently for being companies having several posts every day. Both seem to try to target very similar groups. From 13-35 because that is the generation that grew up around entertainment and is more open to spending time and money watching, and playing.
They both have direct support from their websites and Xbox has it from their twitter. IGN doesn't have any social media support. Overall I feel both are very effective for what they are being used for. I think they are using them to boost their already big presence by advertising themselves.
