Pokemon Fans please Help?

I've owned every pokemongame since red and blues days and the last game i picked up was leaf-green. I kind of forgot about the series till my cousin found a DSlite that some kid thought was broken. (He tried to hack it and "bricked" it) i fixed it and decided i was bored of the legend of zelda phantom hourgl so i picked up pokemon pearl. I am lost! Not in the game, but where the series went. I dont really know the new pokemon or how many there are. I hear already that theres a "platinum" version or something. I hear all this talk about "Gratina" or whatever...Help!? oh and are there like evolved versions of the Regis bros from leaf-green? and on youtube, there like a hack to get the legendary pokemon "Ac-something" i dont remember the name! How many legendaries are there after leaf-green???? Hellppppp oh and does the series still show on like the CW on saturdays any more? i think its only on cartoon network but even so, how did it end on the CW or kids wb or whatever?