A few weeks ago I drove down to Jacksonville, Florida, to participate in a day of gaming and 40k nerdery (that is a word!). The week that proceeded it was a flurry of model building, basing and priming. I didn't actually get any more models to a finished state, but at least it wasn't a Grey Tide swamping the enemy there!
While I didn't get to face off against +Christopher Bergeron and his heretical followers of Horus, it was fun to watch one mixed 30k/40k game and participate in a 40k team game. Any chance to move models, drink beer and eat good food can't be passed up! Even though it was 6 hours of driving for 8 hours of 40k, it was worth it in the end to force me to build a lot of the units I had been amassing bits for.
You can't be afraid to build your army while waiting to perfect a paint scheme, or to design the perfect magnetized/pinned weapon plan. Just jump in an build what you want (or need) right now, and worry about finding parts for your next seven projects LATER!
(Yes, I was hoarding an incredible amount of Mk6 parts for when I would decide what to build... fool!)
Anyway, are you wondering why I call it the Grand Army of Shame? Well, once I saw the beautifully painted armies of my opponents paired off against my primed horde, it was nothing short of SHAMEFUL! Needless to say I have my priorities straight for the next month.... PAINT!