It's not a very good example of an IQ test. MENSA has a sample test of 30 questions on their homepage, and that of course is much more realistic. The one linked above has no visual/picture questions and fill-in-the-blanks that other IQ tests have.
Also, here's a detailed breakdown of the high scores I found:
High IQ & Genius IQ
Genius IQ is generally considered to begin around 140 to 145, representing ~.25% of the population (1 in 400). Here's a rough guide:
115-124 - Above average (e.g., university students)
125-134 - Gifted (e.g., post-graduate students)
135-144 - Highly gifted (e.g., intellectuals)
145-154 - Genius (e.g., professors)
155-164 - Genius (e.g., Nobel Prize winners)
165-179 - High genius
180-200 - Highest genius
>200 - "Unmeasurable genius"
More notes on High IQ and Genius IQ:
Einstein was considered to "only" have an IQ of about 160.
Mensa is a society for people with high IQ, in the top 2% (1 in 50).