I got into a slightly heated discussion over this with another guy once, and in the end we kind of agreed to disagree.

For someone like me it derives from digital pinball where they always seemed to be referred to as 'tables' rather than 'machines' in games - I guess because you don't actually have the physical machine in front of you to play. You just have the playfield, or the table.

I posted a topic once on another site using 'table' and this guy just nitpicked at it 'Table, whats pinball table?' 'You know...a machine, table, whatever.' 'If you walked into a bar round these parts and asked them if they had a pinball table they'd have no idea what you were talking about, it's a machine.' At this point I just kind of went 'Okay guy.' and gave up. I couldn't fathom that someone would have no idea what the difference between referring to it as a 'pinball table' and 'pinball machine' would be and he maintained if I kept calling it a table I'd just get goofy looks because nobody would know what I was referring to. Hell I could probably ask 'Got a pinball?' and they'd know what I meant!