I am pretty sure that test is total BS (it gives quite high scores doesn't it). 124 is well above average, over 140 is serious stuff, like I think having an IQ of 140 is the MENSA requirement.
The reason this test is BS, is that it asks for your age at the start and then clearly adjusts your scores at the end according to that. In reality, I believe there are different tests aimed at different age groups. Also in real IQ tests, there is a timed element and how quickly you complete the test is a factor. As nice as it would be if it was true, I highly doubt that 3 random people commenting on a TSR thread genuinely have an IQ of 140+ (mine was 144)
Even real IQ tests aren't that important, it's one specific form of cognition and people with high IQ's aren't always successful as well as there being a whole bunch of people with lowish IQ's who have been successful through the power of hard work.
Despite it's drawbacks, I would like to get my IQ properly tested at some point - though I find it unlikely that it's gonna happen.