Keeping in sync with the block-chain has been a struggle over the last few versions of geth, including 0.9.28, 0.9.30 and 0.9.31. Sooner or later, every computer (although, strangely, some computers more than others) will fall behind, as compared to stats.ethdev. Sometimes, syncing stops entirely, and sometimes it is just limping a few blocks, or a few dozen blocks behind.
I don't know what magic technology is behind the beautifully designed stats.ethdev web-site, but I wish I could have some of that goodness in the next geth installment.
Or is it all just a question of manually tweaking the parameters in order to connect to the "good" peers, and avoid the "bad" ones?