Ok, let me start this off by stating this is not a flamebait thread, nor do I want any childish arguing. No 3DS or PSP2 "IZ DOMDZ". Just good discussion. We're a pretty adult site here, so I think we can do it. 
Let me also state that I am not actually bashing the 3DS here. In fact, I think it's a pretty neat idea, and if none of the things I write here happen, it should end up seeing the same level of success as the DS. Ok, let's precede.
Now, recently there has been much talk about how the PSP2 is going to have a rough time trying to compete with the 3DS. Mostly due to cost and not utilizing glassless 3D. But since we know little about the PSP2, let's turn it around and look at the 3DS, which we know quite a bit about. I'm going to basically give some reasons that the 3DS may not see a huge success, as well as what Sony can do to counter them. This should be good speculation until the PSP2 is finally announced.
1. Battery Life. Nintendo has recently given out the battery life expectations for the 3DS. After a 3 1/2 charge, it should give you 3-5 hrs of charge. Now, some originally speculated this could be a worse case scenerio, so battery life should be around the same as a DS. But, that's not the case, as Iwata himself said that the 3DS would "require more frequent charging" and suggested that Nintendo should get out the message to charge your 3DS "as soon as you return home." Nintendo also states that these are just approximates and may actually be less "depending on operating conditions." Now if this is true, and most player end up seeing 2-2 1/2 hrs on the higher brightness settings after a 3 1/2 hr charge, it is going to turn some gamers off. Not only that, but rechargable batteries have their own recharge life. Which means with more frequent charging, batteries are going to weaken and die quicker, maybe after a year or so only giving you 1-1 1/2 hrs of play on a full charge.
Sony's Counter: This is pretty obvious. Have the PSP2 ship with a bigger, better battery and/or use lower energy parts. If Sony can do this and provide a battery life of 8-10 hrs, with the worse case scenario being 5-7 hrs, then I believe they could win over quite a few gamers questioning which to buy.
2. Screen Durability. Nintendo has decided to go with a newer 3D technology that doesn't require glasses. Because it is new, I haven't been able to really find any info about the kind of expected durability of the screen required to produce the 3D effect. Is it something that will easily break, or maybe no longer remained calibrated as the 3DS is carried around, or will the second parrelax LCD screen burn out quicker if people are constantly adjusting the 3D slider to safe battery life or if their eyes become tired?
Sony's Counter: Sony seems to be going with a tried and true method of just a normal LCD screen, albiet in HD. Considering these have been around commercially for 2 decades, the tech has advanced/improved quite a bit, so minus you smashing the PSP2 or taking a knife to it, it should last for years.
3. Control. While the 3DS has added an analog stick, the constant complaint about the PSP only having one has taught me that people prefer having two. Ever since Sony released the Dual Analog/Shock, everyone has adopted to this form of controller. And why not? It offers greater control of the camera in all forms of games, be it FPS's or 3D platformer games. The DS has an alternative to this, using the stylus and touchscreen as a right analog stick. However, in my opinion, this makes holding the DS awkward and limits easy access to buttons on the right side. I just think this is going to limit the 3DS, considering they are going to start aiming for 3D movement as opposed to a lot of the 2D gaming we have seen on previous Nintendo handhelds. This also just relegates the analog stick to being only an alternative to the D-pad, instead of the main input for movement in all games.
Sony's Counter: They have finally answered the calls of millions of gamers and put a second analog stick on the PSP. Well ok, it's successor. But this will not only offer great control as a stated above, but also offer a look and feel almost every gamer is used to. It should also make holding the PSP2 more comfortable at all times. This, coupled with its better graphics, could make this the HD gamers go to for handheld gaming. Especially if Sony gets some COD and Uncharted love on this baby. Or new IP's of the same genres.
4. The 3DS is most likely going to be shipping for $249-$299. Considering Nintendo has put off announcing the price for so long, I'm starting to think it may be $299. Of course, normal Nintendo customers aren't used to this price, so any negatives about the product are going to be looked at even harder, since they are now paying a premium price and will want the best in every aspect.
Sony's Counter: Sony fans are pretty used to paying extra for a litle more power under the hood. Most, I believe, are ready for them to announce the PSP2 for $299. It's just a given it would be around that much, especially since the PSP was $249 at launch. I personally think Sony is going to shoot for that price. If the 3DS is $249, it won't seem that bad for that extra power. And if the 3DS is $299, then that's even better for Sony. Sony may even shoot for $349 if the 3DS turns out to be $299. Again it won't seem that much more, and it would allow Sony to make profit, since with a price of $299 I would imagine they were taking a small hit or just breaking even.
Well, I think I've gone on long enough. I do realize there are probably more points than these, so if anything is brought up in the replies, I'll comment on them.
