I know it is nothing new for the discussion of this potentially leaked ruleset (herein refered to as the leaked rules) but I wanted to share my experience with a playtest of it.
A friend and I really wanted to try it out so we read through the rules quickly enough to start playing and decided on two 500 point army lists that would provide a diversity of unit types to help get a feel for the new rules. I believe we had 505 points each but weren't being too limitting on this...
5 man assault team w/ lightning claws
5 man sniper scouts
5 man scouts in speeder storm
Captain on bike w/ relic blade
3 man bike team
5 man scouts w/ bolters in speeder storm
twin auto cannon dread
We played on a 4x4 table with no terrain to avoid any confusion (wanted to take the rules in small bits and I was really under the weather and didn't want to concentrate too hard).
I won the roll to choose deployment sides and we placed 3 objectives on my half of the board. Bidding commenced and I won with a bid of 3. I believe my opponent took something to make his deepstrike more precise.
I deployed everything in a box and my opponent deployed nothing.
With nothing to shoot at, I moved each unit 1" to increase their evasion rating and said go.
His snipers deployed via infiltrate outside of 18" and unloaded on my bikes. One round got through and I lost a biker.
I charge his scouts with my bikes and wipe them out.
His storm successfully arrives via outflank and and the scouts inside charge my bikes. We spend some time learning how directed attacks work and realize that relic blades cannot do so. This is sort of a negative to choosing one for so many points. I lose another bike and he loses 3 scouts.
I kill one more scout (the sergeant remains alive do to the new 5+ invul granted by a power sword) and lose my last biker. I stun the storm and pass the turn.
His jumppack team with korydae arrives and lends itself to the close combat going on already. Because I'm already locked in with my captain, his team assaults at I10. My captain dies to some crazy lightning claws.
My storm moves 6 and all the bolter marines inside fire with the new rapide fire rule and manage to kill the last scout. I again shoot the speeder with my dreadnought and do nothing.
He realizes that we have forgotten about objectives and moves onto one with his assault marines to score a point. Korvydae runs across the field and smashes my speeder to bits.
My scouts and dreadnought make one valiant last stand shooting at Korvydae before each are in turn wiped off the table on this turn and the next.
I'm sure we played a couple things incorrectly but all in all the game feels VERY much the same. A lot of the rules were rewritten in a much more clear way (I feel) that should remove a lot of implied rules. It also seems a lot of "sub sections" from 5th were done away with for clarity. Movement was redone which feels a bit confusing at first but all units essentially get the same move distance that they had before. The most important part of this though is all of the random movement distances are gone. No more 2D6 etc. This is great and removes the bad randomness that was there before.
Deepstrike is far more controlled. This is a win and you can assault afterwards though if you're close enough to do so the enemy gets free shots at you. Very cool.
Sergeants feel a lot more important than just models with access to wargear. Having the ability to choose which enemy casualties are removed from a wound group is awesome.
Wound allocation was made far more clear and less abusive.
Assaulting before shooting and the new Initiative 10 close combat thing to represent suprise/readiness really open up a lot more tactical decisions instead of just blasting every unit in an army into another and then charging. Now if you dont' wipe the unit out, you can't shoot it.
Anyway I won't be playing 5ed anymore at my home and will be using this ruleset until GW releases their final copy. If the GW copy isn't as good, this may just be my new ruleset. The entire game while small, was far more cinematic and intuitive to me. No more excessively powerful coversaves, the ability for units to actually hit the broadside of a barn reliably (marines hit a stationary landraider on a 2+ for example) and units like space marine captains hitting guardsmen on 2+ in close combat are just a few small things which just make sense. I encourage everyone else to give this a try it was the most fun I've had in a 40k game in a while, despite all of the flipping I had to do through the rulebook the first time around.