We have collected data around the world: from China, Greece, Chile, Indonesia, Russia, and Aboriginal Australia.
What we have learned is that people who speak different languages do indeed think differently and that even flukes of grammar can profoundly affect how we see the world.
Unfortunately, learning a new language (especially one not closely related to those you know) is never easy; it seems to require paying attention to a new set of distinctions.
Whether it's distinguishing modes of being in Spanish, evidentiality in Turkish, or aspect in Russian, learning to speak these languages requires something more than just learning vocabulary: it requires paying attention to the right things in the world so that you have the correct information to include in what you say.
It's possible that everyone thinks the same way, notices the same things, but just talks differently.
Believers in cross-linguistic differences counter that everyone does not pay attention to the same things: if everyone did, one might think it would be easy to learn to speak other languages.
I often start my undergraduate lectures by asking students the following question: which cognitive faculty would you most hate to lose?
Does learning new languages change the way you think?
Humans communicate with one another using a dazzling array of languages, each differing from the next in innumerable ways.
Do the languages we speak shape the way we see the world, the way we think, and the way we live our lives?
In Russian you'd also have to include in the verb information about completion.
If George read only part of the book, you'd use a different form of the verb than if he'd diligently plowed through the whole thing.
Most questions of whether and how language shapes thought start with the simple observation that languages differ from one another. In Russian you would have to alter the verb to indicate tense and gender.