I just finished college (US degree- a Bachelor's program) and had a few classes that had open-Google tests. I did well with those- but they were pretty much always structured such that you HAD to think on your own. Yeah, I access to reference material, but I had to actually convince the professor that it was my own work and my own words. It definitely did help bridge the gap between rote memorization and application just a formula or such and being able to pull information you don't have memorized together.
Some things are realistic to want memorized, such as how to configure your computer and network sufficiently to be able to get to the web, but other things were obscure enough that I don't remember how to do them after passing them on the test- but I DO know how to find the information I need. At least at my school, the average technical student was taught how to perform the tasks on the conceptual level, and a few specific implementations. Beyond that, we were expected to use every reference material we could get our hands on, be it Google or a book.
Personally, I felt that open tests like the sort described tended to do a far better job of letting me show what I had learned in the course than a lot of other exams, which frequently were multiple choice or short answer of a memorized problem/solution.
In a business environment, which is usually more valuable to a company: someone who learns the specific tasks that are needed on a daily basis easily, and can use reference material when needed, or someone who can do a certain set of tasks extremely well, but needs a lot more time and hand holding to get up to speed on anything else? I've definitely noticed that a lot of companies I was interviewing with wanted someone who could use reference material more.