Well I did say that "the hobby" was probably a post all on it's own. Before I get to my musings on the hobby in any detail I need to lay out some definitions.
Tabletop Games come in all shapes and sizes. For the purposes of this blog these are the defintions I'll use.
Board Games (BG) - Any game that uses a shared board for the purposes of play. e.g. Settlers Of Catan.
Card Games (CG) - Any game that uses cards as the core mechanic without having a collectible or trading element at that core. e.g. Sentinels Of The Multiverse or Munchkin
Collectible Card Games (CCG) - A card game that has at the core of its design the nature of customising and collecting cards to build variant decks using random packs of cards. e.g. Magic The Gathering
Living Card Games (LCG) - I struggle with how to categorise these so will keep them separate for now. LCGs are the same as CCGs except that the variant decks are built using static packs of cards. e.g. Star Wars The Card Game
Dice Games (DG) - Any game that uses dice as the sole element of play. e.g. Zombie Dice
Collectible Miniature Games (CMG) - A miniatures game that has at the core of its design the building of lists using randomly collected miniatures. e.g. Heroclix
Roleplaying Games (RPG) - A game where the action is largely taking place within the imagination of the players and interaction is more abstract than in most of the other formats. e.g. Dungeons & Dragons
War Games (WG) - Also could be classed as Non-Collectible Miniature Games. A miniatures game that has at the core of its design the building of lists using static collected miniatures. e.g. Warhammer 40,000
All of these roll up into the top level definition of Tabletop Games for me. They are all played on a table and they are all games.