The ES has been Lexus best selling car and 2nd in sales to the RX for years. The 2007-2012 sold in similar numbers when new with only one model. The new gen continues that trend. They obviously know the entry level luxury car market.
Impressive when you consider the TL, Infiniti G, 3-series, and Audi A4 are all flat to down. C-Series and ES are clearly picking up market share.
That said, some of this is riding Toyota/Lex's huge lead in hybrids. Can't say I'm ready to trust a hybrid from anyone else.
Also will be interesting to see how '14 goes with the Acura TLX and Infiniti Q50 launches. C-Series already pulls in a younger buyer than the ES, and the Q50 will have the interior tech that under 50s like me expect now, and which is severely lacking in the ES. No touch screen, but a CD changer? in 2013? Really?
I believe Lexus hybrids account for only 25% of their ES production, so the sales increase is more likely due to to new and improved model, lower end of the production year sales and reduced production of Lexus and Toyota due to the tsunami in Japan.
Toyota and hence Lexus has been the leader in hybrid technology with longevity on their side. I don't see any change in the near future, and have confidence in their products.