Mucking Rules... Should I have won???

I was in a situation tonight where I was heads up and my opponent mucked his cards after I flipped my cards over, but he quickly took his cards out of the muck and was still able to win half the pot as it was a split... Here's the situation:

At a $2/$5 table, I had J 10 hearts on the big blind, raise was $20 preflop... There was 1 caller and me, so 3 going into the flop... Flop came Q 10 8... I was first to act and bet out $30 (about half the pot)... One of them called me... Turn came another 8... I checked and so did my opponent... River came rag (like 3 or 4)... I checked again, he bet out $55... I called his bet and he said that he had a pair of 10s.... I then flipped over my J10 and he said "you got me" and threw his cards about a foot in front of him (in other words, he mucked), then literally 2 seconds later, he realized it was a split pot and took his cards back out of the muck and flipped over his 10-9 before the dealer even touched the cards...

I was wondering if that is legal what he did??? I even asked the dealer, but the dealer said he didn't muck... I believe I should have won the pot... The pot was a little over $200, so I believe I got screwed out of about $100... He had a friend at the table to defend him and everything... I look back and wish I would have called the floor over and let them decide instead of letting it go... Oh, well... Still made 6 bills tonight as there were plenty of fish.... What do you guys think?

I would of thought it was too late for him,its like he folded and then changed his mind.

He mucked, should have called the floor.

Definetly should have called the floor over. Once your cards hit the muck, they are dead.

Yea, just what I thought... I didn't want to complain that much as it was a split pot, but a muck is a muck... Should have called the floor over... I'd be $100 richer if I did...

Yea man you dont grind it out for hours for no reason, your money is your money!

From Roberts Rules of Poker

1. Your hand is declared dead if:

(a) You fold or announce that you are folding when facing a bet or a raise .

(b) You throw your hand away in a forward motion causing another player to act behind you (even if not facing a bet ).

DISCLAIMER: Most B&M places do not adhere to Roberts Rules of Poker, but their own similiar variation.
Another thought:
I have heard tell of places that keep a hand live until it actually goes into and touches the the other folded cards - "The Muck" pile.

So you did not call a super over - you owe it to yourself to at least ask for a clarification and insure they don't have some funky rule that someone can exploit.

If the cards didn't hit any other cards he's probably within his rights at most places to turn them over. You could have still called the floor over to double check but more than likely the result would have stood.