These are numbers I figured out for a discussion in another thread, but I like number crunching so I'm going to try to follow this through the holidays in its own thread.  Basically, it compares last year's 360 sales after the price drop to this year's PS3 sales after its price drop and slimification.  Also, I'm including the sales of the "also ran" console from each year to compare how they held up in the wake of the increased sales of the competition.  The final column shows the net effect on the 360/PS3 gap.  I'm not following Wii sales here even though there was a price cut this year because it wasn't the same sort of momentum changing/disrupting kind of thing that has happened with the HD consoles.  Let's just say Wii has amazing sales all the time and leave it at that.  Also, I realize that 360 also had a price cut of sorts this year (and PS3 last year) but this is about the main ones which took effect during the first week of September in each year.

So far, the PS3's price cut has had a more dramatic effect than the 360's last year, but the 360 effect was more of a slow burn and really took off from Black Friday onwards so I expect the PS3's "lead" here to be cut down substantially in two weeks.  Hopefully, a somewhat tight race will emerge.  Would be interesting if the two years just end up negating each other in terms of the gap (but I think that's unlikely).

I'll make a new chart each week instead of just updating the original post.  Basically, I intend this thread to be for numbers junkies by a numbers junkie.  It's not meant as any sort of advocacy so please avoid turning it into that.  Predictions and such and comments about the numbers themselves are welcome of course.

I should also point out that the second column of numbers is something of an "apples & oranges" comparison as it looks at PS3 numbers going into it's 3rd holiday season vs. 360 numbers going into its 5th holiday season (which I actually thought would put the PS3 numbers at an advantage, but see for yourself...).

These are worldwide numbers, obviously.  I did figure everything out by region at first but that took forever and I'd never be able to do it on a weekly basis.

The number in the bottom right corner is the net effect of both years combined on the 360/PS3 gap.  Basically this means that PS3 has made up the ground it lost for the period in 2008 and then caught up another 946,301 units.  Like I said, this number may change considerably beginning with the Black Friday week.

I'm also going to do a chart for the specific week in addition to the cumulative chart to show the effects of a particular week.  I realize that this is probably of more interest to people anyway at specific times like Black Friday or the launch weeks of big games.  Anyway, here is the first chart.  In the future both charts will be combined in one post.

So here you can see that even though the price cuts have helped PS3 more over the cumulative period from the start of September, for this particular week, the combined effect of last year and this year was to increase 360's overall lead.  This can be attributed to the MW2 bundle keeping 360 sales high despite the PS3 momentum.

Next week is the final week before Black Friday.  The corresponding week in 2008 saw 360 sales rise to 406.3k units.

This thread is interesting, and I won't let it die.

From here on in it will probably be close (PS3 numbers and last years Xbox numbers). I Think the PS3 will have the edge with upcoming numbers and with a million lead should easily beat Xbox 360's last years numbers. Mabye we should take a close look at the Americas after black fridays numbers are in.

Thanks for the interest in this.  I'll keep updating it through the holidays at least.  How interesting it becomes depends on how close things get.  That's why I started out by breaking things down regionally.  In Americas things are considerably different from everywhere else.

Digging my notes out of the recyling bin, I can give you the following cumulative numbers for Americas through Nov 15:

360 2008 = 1,074,160, while PS3 2009 = 1,212,294 so PS3 has a very slight lead in sales (47,134 units).

BUT

Whereas PS3 kind of collapsed in Americas last year (640,910 units) after Microsoft's price drop, 360 sales this year have held up pretty well and with the strong sales of the last two weeks are now almost as good as last year (1,062,568 units).

So... while PS3 has gained 149,726 on the 360 since September, the combined effect of the two years still has the 360 up by a net 374,524.

EDIT: Changed the final comment which was misleading.  I'm confusing myself even!

next week we'll get a better idea of how thing are going to turn out.

Walmart promotional sale helped 360... it was selling less than PS3 2008 prior to November...

It will be interesting to see how this plays out. My gut feeling is that from now to end of year: 360 2009 > PS3 2008 and PS3 2009 ~ 360 2008 (some weeks up some weeks down). The next 2008 360 result is 406K. I'm not at all sure PS3 can get up to 406K this week, that will be a 24% increase, can the seasonal lift give PS3 24% post the modest boost from the biggest multiplat game launch of all time (albeit it was never going to be a huge system seller)?

It's a smaller jump then what 360 had to do that week last year. So I think with Japan there is a good shot. Does the Assasin's Creed bundle come in this week?

I'm going to do an Americas chart in addition to the world chart this week and next.  I may possibly continue doing so even after the Black Friday numbers come in.

World chart first.  Quick summary: PS3 did not reach 360's sales of 406k from 2008.

In all ways, not a great week for the PS3 price cut effect compared to last year's 360 price cut.  PS3 didn't match last year's 360 sales and this year's 360 sales exceeded last year's PS3 sales.  I think this is the first time this has happened since the Slim was released.