Error on upgrade to 6.x-1.2

Got these errors in log entries after running update 6001 in the process of updating to 6.x-1.2 version on the localhost.

include_once(sites/all/modules/emfield/contrib/emvideo/emvideo.theme.inc) [<a href='function.include-once'>function.include-once</a>]: failed to open stream: No such file or directory in C:\wamp\www\drool\includes\theme.inc on line 613.

call_user_func_array() [<a href='function.call-user-func-array'>function.call-user-func-array</a>]: First argument is expected to be a valid callback, 'theme_emvideo_formatter_video_preview' was given in C:\wamp\www\drool\includes\theme.inc on line 617.

I activated the thimbnail module and the third party thumbnails for the youtube, metcafe and vimeo videos seem to be working all right. So can these error messages be forgtten?

Also, is it alright to use the current dev (July 25) version on a production website?

Thanks.