Unlike LG's wacky BL40 ultra-widescreen Chocolate, the newly-spotted BL20 is more obviously from the Chocolate lineage. It's a non-touchscreen slider with haptic feedback on its touch-sensitive buttons, and actually features an interface not dissimilar to the BL40.
It's missing some of the more advanced features the BL40 boasts, notably an accelerometer, but should be a cheaper and smaller alternative to the BL40 if and when it's eventually released. We've got no info on price or release date, but we'll update when we do. [Engadget]