alt Hacker News> in Spanish, gender is pretty easily determined from the word ending 99.9% of the time unless it's a Greek neuter, and there are only a few of those.
Isn't that 99.9% referring to the reliability of spelling heuristics for the words that match a heuristic? For example, the -o and -a spelling heuristic reliably indicates gender something like 99+% of the time, but only about two thirds of Spanish nouns end in -o or -a. There are a few other suffixes with string gender indication, but even then I think you can only account for like 75% of Spanish nouns.
I'm strenuously disagreeing with the 75%, especially in terms of usage. Almost all nouns that end in -a (unless they're Greek neuters), -ión, -umbre, or -dad are feminine. Otherwise, they're masculine.
There are plenty of exceptions, but 1/1000 words sounds about right to me.
edit: my point was that French is far more chaotic than that, and it does cause mistakes. Goes with the general observation that French is easy enough to read, but hard to write.