John Zdanowski (AKA Zee Linden) has published Linden Lab's Q4 Second Life metrics from 2008 mixed with an annual summation. It reflects a considerable number of positives, but reads a bit like one of the paradoxes of motion from Zeno of Elea.
There is so much spin on these figures that you'd be well-advised to keep your fingers clear. Yes, Second Life experienced significant growth during 2008, and there was indeed growth in Q4 as well. None of the figures are wrong (except for the figures reported for reduction in land, which are credibly refuted elsewhere), but like Zeno the time frames used for the comparisons jump between using comparisons between years and quarters. As such, closer reading gives a different impression than a quick skim.