I love my white cabinets and it would look good with grey. The trick is are your features in metallic silver/chrome or gold? If gold go warm if silver go cold. Mind you don't take all of my advise... My floor for example is a warm ivory/beige and my walls are a muslin colour by Benjamin Moore. The countertop is a slate black with flecks of a coffee colour in it made of laminate that looks like granite. The appliances are white and the fixtures are metallic. The only thing we haven't done is the backsplash which will either be travertine subway tile or white marble with some black in it... Kind of got lost in the picking. So you can go either way. Just try to match your walls with your floor but give the walls a lighter colour than your floor.

Natalie, there are warm greys and cool greys like these pictured. I don't really think that either one dictates whether to use a white or off white because you can mix the warm with the cool.

Alison, are your cabinets SW Pure White?

Kinda messy in my kichen but this is an idea of what it looks like

I didn't photograph the whole thing because it needs a good de cluttering lol

And that old light in the dining room is going lol no worries