Well I don't see the point in separating it by home console and portable console. Both compete on the same market with the same potential consumers. I guess only difference would be is that a home console could be seen as "1 per household" and portables as "1 per person" but considering the best selling system is a home console it is hard to see that as completely relevant.
It does seem the DS will pass up the PS2 in sales by about August or September timeframe if everything goes smoothly which there is no sign that it won't. Shipments will surpass it sometime at the end of the year.
I do agree with another notion that PS2 sales and shipments don't seem to match up all that well which could potentially mean we are under tracking PS2 sales over some extent of time in its lifecycle or potentially a misunderstanding of PS2 shipment numbers (has been out for 9 years).
I do think the most important thing we can get out of this is timeframe though. Consider how long it took PS2 to accomplish this and how long it took DS to accomplish this. That is where the main difference in comparison is if you ask me. DS has just sold at rates that are unheard of.
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