I just found this interesting website where the owner has collected hundreds of Google Logos. Its really amazing to see how many ideas these guys get for a single logo.... just amazing. take a look http://www.google-logos.com/
Not sure about it. You need to check that website and their Terms of usage. May be contact them and ask for their permission.
NOOOO Google LOGOs are copyrighted by google itself u need to take permission from Google to use these LOGOs READ http://www.google.com/permissions/guidelines.html
I don't think google is going to sue the guy for highlighting their logo...... but I could be wrong...
Officially I think it would be a copyright issue, but then I seriously doubt if Google intends to pursue as it wasn't use to spoil Google image in anyway. It is actually helping to promote Google, not that Google needs much promotion. Anyway thanks to the OP for bringing out such a unique site. It is really interesting to see all those variations. Those Google guys are real creative!
Maybe if the site you are going to use the logos on is something bad about google then they may sue you but if your promoting there site they won't mind
Right well Google like always is way ahead of people Every Google logo ever used here http://www.google.com/holidaylogos.html