No they publicize the mobile sales figures often. I think they did not want to hype up tablet sales figures because for them this product line was a complete market and R and D research experiment, if the tablets had failed to sell I don't think it would have been the biggest deal.
They are gathering data and observing this new community focused product development cycle, their resource inputs for this semi successful product line have probably been some of the smallest ever put into one of their devices.