Holy cow! It sounds like you have one very smart cookie!!
My eldest knew his phonics sounds and complete letter recognition by approx. 12 months without real instruction. He began combining sounds into easy words by about 18 months (cat, hat, etc.) and was able to do easy readers by 2. We knew that his verbal abilities were ahead of peers but didn't fully realize that the understanding of letters and sounds (and eventually reading) was so abnormal at his age.
He's now approaching his 5th birthday and is an excellent reader. I'd guess that he reads on a 6th grade level++ but (of course) 6th grade material often isn't appropriate for him. He loves to read and regularly finishes chapter books in an afternoon. He tests above the 99.9 percentile on verbal IQ and ability tests. For his "school work," he does 3rd grade language arts and his spelling is commensurate.
Handwriting is often his limiting factor(it is age appropriate & a challenge).
He is working well ahead of grade level on math. Although he seems to understand difficult math concepts, his math/quantitative ability is very obviously not on the same level as his verbal ability. It is just not his passion. Test-wise, he's 99.8 percentile in quantitative IQ. After reading the other posters, I'll be curious to see how his ability develops as he ages.
FWIW- my DS reads everything- including a lot of book series intended for girls. At his age, he doesn't care! So I wouldn't be too concerned about gender for a while.
Also, a speech therapist administered a PPVT to our son when he was about 2 and he scored at approx. 99.7% -which continues to fall within the range for his later verbal skill assessments
Good luck!!!
P.S. We found the book
Smart Boys by Kerr and Cohn very helpful.