Recently bought a new battery for my N900 since it's still my daily runner, the last good original BL-5J started having issues and my old Polarcell dropped to 980mA.
Battery is Patona from Amazon, last measured discharge = 1537mA (usual bq27k stuff). I got through one day with no recharges, a thing that made me very happy.
Let's see now for how much time the battery will keep this performance...