If there is one mechanic above all others that I am immediately drawn to its tile placement. I enjoy starting with nothing at all, or just a blank board, and seeing what I have created at the end of the game. In some tile placement games, like Carcassonne the City, you end with a beautiful visual of a completed city. It's fun to watch the reactions of other players at their creation. I see the pleased look on their faces as they look at what they and the other players have designed.
Hallmarks of Tile Placement Games
Tiles can be used to score points, extend the playing area or map, or change the board. There are many shapes and sizes for tiles. Squares, rectangles and hexes are common.
These tiles are placed under specific rules for that game. In the game dominoes, for example, the bones are placed so that matching numeric values touch. In the game Blokus players must place the Tetris like tiles so that they don't lie adjacent to other tiles, but touch the corner of another piece already on the board. In some games the orientation of the tile is very important. In the game Cable Car tiles must be placed so that are the buildings pictured on the tile are facing the same way.
Who places the tile, and how the tile is used, differes from game to game. Most games have the current player placing and using the tile. Others, such as Cable Car, allow multiple players to use the same tile. Once these tiles are placed they usually are not moved for the rest of the game. Of course there are always expections to these rules!