besides making houses, clones and trees out of nowhere.. what is it's big effect during battles?.. and if someone other than Madara right now has wood release.. is it enough to defeat him?.. really.. what's so special with it?..
Well, wood release has been shown to be used by a single shinobi, or any shinobi who can transplant (LOL, plant) themselves with his DNA. This makes it the most rare Kekkei Genkai (even rarer than the Rinnegan, as that was awakened at least twice, and transplanted once. I don't count transplants as actually having it for rarity).
Not only is it the most rare KG, but it has the power to tame Bijuu; massive creatures who have been shown to only want to destroy when not trapped in a jinchuriki. This shows that wood release has some sort of ability to calm beasts, or maybe exert chakra to supress power, or something along those lines.
If another ninja had wood release (such as Zetsu, or Yamato), I doubt they could beat Madara unless they had a way to fight the Rinnegan as well.
Wood release also seems to be the most versitile KG, IMO. It can be as fluid as water when the jutsu is being made (like making pillars, ect.), but is as sturdy as earth when finished, or while being made (maybe harder than some earth techs). It can be used to make small tools, clones, or whole forests (as shown when Hashirama made the forest around the Hidden Leaf).
For any further quesions on Wood Release, consult Narutowiki.