A contrasting worktop can look lovely - I have high-gloss white cabinets with a matte black countertop. I've also seen mid-to-pale wood with a high gloss black, and mid-to-dark wood with white marble-style. All look great.
Go to a couple of kitchen showrooms, or even look at magazines or online to see various combos.
With the oak cabinets, I would opt for either a totally matt black worktop or a glossy black - get a sample of both and see which works best. I would advise against brown/creamy worktops - far better to go for a contrast/statement worktop that wont date (i.e. black) even if you eventually change the tiles.
I can't see white worktops looking great with oak cabinets - I think you could tire of this look very quickly, especially as you have beige tiling.