Instead of the Premiere XL and Premiere Elite, they're called the XL2 and XL4.
First you had to get used to saying Istanbul instead of Constantinople and now this. TiVo has renamed the Premiere XL and Premiere Elite to the Premiere XL2 and Premiere XL4 respectively. The numbers, of course, refer to the amount of tuners built in to the device.
According to Engadget's Daniel Cooper, the renaming is an effort from TiVo to avoid confusion in its product lineup. Renaming the Premiere Elite makes sense enough, but calling the Premiere XL the Premiere XL2 isn't exactly straightforward.