The followup to the Sony Tablet S may have appeared on a benchmark result submitted to Nenamark according to an article published by Netbook News.
The metadata associated with the result shows that the tablet is called the V150 (or at least, this could well be its internal codename), it ran on Nvidia's quad core (or four-plus-one) Tegra 3 processor which was clocked at 1.4GHz and was powered by Android 4.0.3 Ice Cream Sandwich.
The tablet reached 59.70 FPS on NenaMark1 which compares favourably with the 42.89 per cent scored by the Sony Tablet S which runs a dual core Nvidia Tegra 2 SoC clocked at 1GHz. The rather small difference could be explained by the fact that NenaMark hasn't yet been optimised for multicore SoCs.
Disappointingly, the V150 seems to stick to the same resolution as the S1, 1,280 by 800 pixels, rather than going full HD or more like the New iPad, the new Acer Iconia or the Asus Transformer TF701.
The S1 has just dropped in price to less than £300 following the release of the New iPad by Apple and the subsequent drop in price (to £329) of the old one.