Well with all the features enabled that I bought the N900 for (3G, GPS, Location awareness, WiFi, Laptop replacement, microB full sized browsing) I never got more than 6 Hrs.
Here's Proof.

I do not think that would make me hate my N900, but with just an additional investment of $8, i.e. a spare battery, things are plenty under control, as seen in Day 2 chart, where the capacity suddenly jumps to 100% near the end of chart.

Well nokia can bundle an addition BL-5J with N900, but I am sure the 'corporate' will never budge on this one