Never assume that shipped consoles have a constant parallel trend to consumer sales.   I can point out a quarter where Sony only shipped 10,000 PSP units but sold 2 million at retail.  The reason this happened is because the quarters prior had shpments far greater than the consumer market was absorbing. 

I can show you a similar circmstance with the X360 a few years back.

Market absoption, warehousing, aggressive speculative ordering, new market channels, transit varriances, etc...all can lead to huge shifts in the gap between sold and shipped.   You cannot just say shipped minus x amount as a constant equals sold.  So you are assuming they are beincing less accurate with their PS3 numbers based on an increased gap between Sony reported units shipped and VGC reported units sold and while it's understandable to wonder why the discrepency, it's not at all an odd phenomenon to those that comprehend how market supply chains work.

You aren't factoring in the fact that the 360 had a year head start, that adds alot more to games then it does to hardware, Sony has outsold the 360 in software sales a few times now atleast one of them was over a whole year (and only that year), thats with VG putting it at 6 million behind, how exactly is that possible? 

EDIT: I thought you might want a link http://www.playstationuniversity.com/ps3-software-sales-outstrip-xbox-360s-ps3-attach-rate-up-to-8-1-3807/ so in 2009 ps3 had more software sales then the 360, not by much, but the 360 was obviously ahead in sales by some amount due to their year head start 

if it was one or two quarters I might agree, but when it's off by 2 million and was off in the same way for a whole year I don't, you can't sell a console if it isn't shipped so of course it has a parallel to sold, constant no, thats where complex calculations come in, at anyrate, ignoring sales is not the way to go

Sounds like me like you are looking at it backwards.  Not so much why is VGC so wide PS3 shipped to sold gap but why are they so narrow on X360 shipped to sold gap?

2 million in transit, warehousing, new markets, on shelves, etc...that's actually not too much of a gap.  X360 is usually also nearer a 2 million difference.  The X360 shipped to sold difference is is more narrow now because they are selling more X360's at retail than they shipping them. 

Does that make sense to you now?

So you are saying they are giving 360 sales it doesn't have instead of ignoring ps3 sales, thats even worse 

Not at all.  I don't think you grasped what I was saying then.

Picture a 2 million unit gap on average between shipped and sold.  Now if sales pick up much faster than the rate they ship units, that gap will narrow.  The launch of the X360 S model is selling much faster than the older X360 models did in previous quarters.  This narrows the gap between units shipped and units sold.

More clear to you now?

But VG chartz had Sony having a bigger gap then MS for 3 quarters in a row, 

Now look back on my earlier posts and put it all together.

Different shipment/sales rates, market absorption, warehousing, aggressive speculative ordering, transit variances, store shelving allocations, new markets, etc...

Far too many factors to consider that can easily account for the gap issue.   As I already mentioned, this has happened before with the PSP and X360...not just right now with PS3.   It's a common phenomenon is market supply lines and happens in every industry on the planet.

they did it for the move.. don't know why they wouldn't do it for the ps3 or other video game hardware

The problem is Xbox 360's first YEAR they only sold about 25-30 million games.. so that means they weren't very far ahead in game sales when the PS3 was launched ( at the time titles weren't exactly oozing from all places as they were getting started and argulably the PS3 has just a smany titles or more on their launch because developers started developing for both consoles around the same time, but PS3 launch was delayed ) .. Fast forward to now .. the 360 library has about 150 more titles then the PS3's ..which shatters another well placed Sony marketing scheme that there aren't many game choices on the 360 which is bogus.. So subtract the games 360 sold the first year and they are still near mid-90 million game units ahead .. not too shabby..

The Xbox 360 ships to places like the congo area which are hard to track as well.. so does the Wii..  The problem is Sony says they shipped this, but they can be stored for weeks or months not moving volume.. this was the case where I live where Sony was saying publicly that Christmas sales were lagging because they couldnt ship enough - yet there are all these units sitting on walmart floors not selling.. What is shipped by Sony, MS, Ninendo doesnt equal what is sold..

Anyone can argue this, but Im going to say by end of fiscal year shipments versus units sold are pretty solid.. So at the end of that fiscal year they can actually see what was sold in dollars and cents.. We have how many fiscal years of underwhleming Sony sales?   Its time for fanboys to face it.. the PS3 will never be the PS2 and its been rumored Sony is burning the midnight oil trying to get their new console out alittle before MS this time.. What did the PS3 have in common with the PS2 ? Not the launch... The PS2 launched 1.5 yrs ahead of the gamecube and nearly 2 yrs before the Xbox 1.. Wow.. No wonder they dominated after the strong lnauch of PS1 !  PS3 is different - lets see launched LATE, launched EXPENSIVE with a media disc which was not YET a standard like DVD... all great combinations for success suicide.. And now somehow fans want a recount ? Lets get real !