Truly, the last time I really cared about raising pokemon and being awesome at it was the GS games, Silver (my choice) was truly one of the games I played front to back.
Loved it.
Ruby, I felt was alright, but it didn't have the same magic, and the world sucked too.
Pearl I felt was much better than Ruby, and some of the magic came back, but most of the new pokemon were terrible (except for Garchomp, Gastrodon, and Luxray, my team and my favorites from DPP era)
I'm not getting Platinum because I really don't care about the new "world" (it's just an added area, right?) or the new form of Giratina (which only exists in that "world"? correct me if I'm wrong). Just seems like a waste to put more time into playing a pretty boring pokemon game anyway.
Eh, I still play Pearl anyway though.
EDIT: I like to "feel" alot don't I? I felt that was nessecary