currently have 58k in mine. bought it in March '07.
I had many minor issues(rattle from dashboard, leakage from coolant hose and radiator, rear view transmitter malfunction, and so on. All was covered by the warranty) but not any major ones yet.
I had my first service done last week since my factory warranty has expired.
Changing engine oil, microfilter, and detail vehicle check came out to almost $800. They found a leakage from the washer fluid tank and quoted me $500 estimated price to change that little plastic fluid container. I told them to forget about it. Anybody knows any decent bodyshop in LA area where they can fix it at more reasonable price???

__________________
'07 X5(E70) 3.0si - Space Gray / Nevada Gray interior
Specs: Premium | Tech | Premium Sound | Comfort Access | Rear Climate | Custom Chrome Plated Grills | Style 168 22s w/ Sumitomo HTR | MTEC Cosmos Blue Bulbs (H8: Angel eyes, H11: Fog light) | BMW 4.8 Chrome extension exhaust tips (will be delivered from Germany and installed in Feb 09)
'05 645ci(E63) - Titanium Silver / Cream Beige Dakota interior
Specs: Fully Loaded.