Pokemon Platinum Version :: Pokemon Catching Guide
Gotta Catch 'Em All Fever!
Of course, the most important thing about learning the differences in a Pokemon version is knowing which pokemon you can and cannot catch. The thing that will probably make all Diamond and Pearl players jealous is the fact that, not only can you catch the awesome Ghost/Dragon pokemon Giratina, but you can still get the featured pokemon from Diamond and Pearl. Naturally, that's Dialga and Palkia, who are both catchable in Platinum.
You cannot get the following pokemon without trading for them:
For the Fighter/Trader in You
Platinum features a lot of useful tweaks to its online and battling systems that will really make your life easier if you love trading and battling over Wi-fi.