Granddaddy Purple's Purple Dream is definitely Blue Dream/Grandaddy purple. If it's just some random Purple Dream strain? It could be a Blue Dream cross with Blackwater, Lavender, Purple Diesel, Purple Urkle, etc. But again, in this case, definitely Grandaddy Purple/Blue Dream.
Myself, I just finished running Kandy Kush (Trainwreck x OG Kush) to quite the success. This is one of the best rounded OG's out there. It has a coffee-ish skunky smell with an undertone of sweetness #noHomo. Great bag appeal smoke. Certainly a top shelf strain, given a decent cure. A good yielder, too.
I also ran a White Fire Alien OG to see what it's about [(White Widow x Fire OG) x Alien Technology (Unknown Pure Afghani)]... It's a definite recommend. Extremely coated. It has a similar smell to the Kandy Kush but without the sweetness. It's a good high... Heavy heavy yielder, as the buds tend towards a sativa growth pattern.
But the reason I comment is because I've also just acquired some GDP x Blue Dream, Lemon OG x Blue Dream, and Blackwater x Jack Herer beans to experiment with (from my underground San Francisco network)... 100+ A-B grade seeds for $100. It's going to be a busy winter into the first of the year! I plan some backcrosses between some of the genetics, too. As a matter of fact, I picked up a few clones of some other killer genetics to add into my gene pool... Here's a few more photos for those interested.
So, Phantoms is a GDP x Cherry Pie cross... Which is actually very similiar to Girlscout Cookies but with a different cross sequence, character emphasis, and minus the Durban Poison. The San Fernando Valley OG genetics speak for themself, and so do the Purple Urkle. For those that know, Purple Urkle is very slow to generate... It finishes about average but it takes forever to veg. to a reasonable size. But! It is, in my opinion, the best smelling Purple out there, smelling almost exactly like grape kool-aid and lemon concentrate. So, I certainly acquired those genetics for the purpose of distilling that smell into one or a few of my crosses. With that said, I won't give away my exact cross sequence... Just know that on top of whatever sequence I'm employing, I also back-salt my beans with a pure (and secret) set of genetics. I'll certainly make a forum post of the results around late-January.
Lastly, to bring it back to the subject of Purple Dream... She's yield's an aggresive amount of wonderfully coated/smelling bud... Especially if it's a predominantly Blue Dream phenotype (yours looks like she's 50/50) .So, definitely let your lady get big and healthy... And most importantly, pollenate her!