"LG released information prematurely regarding the minimum processor upgrade requirements for the LG Optimus. Google recently announced the Gingerbread platform and has not yet published the Gingerbread Compatibility Definition Document (CDD) or the public branch open source code. Once the CDD and the source code is public, LG will evaluate the upgradability of the Optimus Series. We apologize for any confusion or misunderstanding. We will alert you as soon as more information on this topic is available."
Google has not published the Gingerbread Compatibility Definition Document and have not opened the public branch for open source code. So, until then manufacturers cannot do much about it. LG also made another announcement yesterday as below:
LG will upgrade all Optimus One smartphones currently using the Froyo OS to the next version of the Android OS, Gingerbread. Details of the upgrade schedule will be announced locally in due course. We sincerely apologize for the confusion and misunderstanding that was caused regarding this issue.
So, LG Optimus one users can rejoice as Gingerbread upgrade is DEFINITE! It's just a matter of time..We will keep a tab for you!