For a brief time, the online retailer Mobilefun had the LG G Watch up for preorder for only $254.99. They had multiple versions listed for several different countries, but since that time the listings have been removed. This suggests the retailer jumped the gun and shared info that LG and/or Google were not ready to share regarding the device. It could also mean that final pricing hasn't been determined.
We can rest assured that we will know something regarding the G Watch sometime today or tomorrow from Google I/O. We will keep you apprised as the day goes on.
Source: Phandroid