The issue with PSP attach ratios is that historically, handhelds have always had much lower tier rates than home consoles. Last gen, most home consoles were near 10.0, whereas GBA was somewhere near 4.0~5.0.
PSP attach ratios for software are NOT that great. It's around 3.0. Trust me, I've checked. Just add up the past oh, 1 year of PSP software history in Japan and divide by total sales then, and you'll get a general, fairly accurate picture.
However, to the PSP's advantage, it does have UMDs that increase attach ratios for a unique type of software to the PSP. I assume the UMD attach rate is around 1.0 for purchased UMD movies, give or take.
Overall, I would consider the PSP, if profitable over its lifetime for Sony, a great succuess. Many people feel its a failure since it's in the shadows versus the DS, but the fact is, the PSP has helped, along with the DS, expand the handheld market. The handheld purchase rates are through the roof - every week, almost 750,000 PSPs and DSs are sold a week. The PSP has sold more than every non-Nintendo handheld (Lynx, Ngage, Game Gear, ect, ect) combined, and it can easily do another 15-25m before a succuessor announces.
So in that way, it hasn't failed. However, it did have alot of foward momentum pre-DS launch, and blew some of it's momentum. It was highly anticipated, and greatly recieved. Honestly, it faces a difficult problem: the fact is, the software SUCKS for the PSP. I want a PSP, but the games just aren't there, unlike the DS. Games that are big for the PSP such as the GTA Stories, MHP, and Final Fantasy itenerations do well because they're big name IPs, but most devs havent supported it as well as they could have.
Likewise, Sony hasn't done enough to develop alot of strong IPs on their own handheld. With God of War, I think they're finally realizing that half of the reason the DS does so well is top-tier Nintendo franchises on their handheld have only but helped. Nintendo has Pokemon, a unique great IP for their handhelds, whereas Sony really has nothing to combat it. Hopefully, Sony can do better, because the PSP has the potential to do upto 75m still in this gen (Im not saying it will get insane numbers like that, but it could if Sony really cared about the PSP).
Back from the dead, I'm afraid.
