Sheesh! I just upgraded to PSP X4 two weeks ago and it has already become obsolete!
Looking at the description it doesn't look like there is anything new or more exciting than X4. Other than a few brushes that never get used I don't see a need to upgrade any further.
LOL...I must be really behind the times! I'm still using X3.
Don't feel bad, I have no idea at all what this is! I have only ever used Photoshop.