[lucianof]

I noticed that Google uses +You in English (as a plug for Google+ if you're not logged in) and +Ich (= +I) in German. Maybe they really just want a three letter word.

Researching further: French: +Vous (polite 2nd person) Italian: +Tu (casual 2nd person)

German seems to be the exception, Googl prefers 2nd person.

[_delirium]

In Google Scholar, though, the link to your own Scholar page (if you've set one up and are logged in) is "My Citations" in English, so they seem to be using it inconsistently between products.

[chromedude]

But then when you have Google+ they change it to +Name (example +Stephen)

[zerostar07]

maybe "+Sie" would be confusable?