It's not a handheld, so I wouldn't track it with handhelds. It's nothing like the 2DS... the 2DS is just a cheap version of the 3DS. 2DS is more like the Vita Slim than Vita.TV. A hardware revision to cut costs and attract new buyers. Vita.tv is a home console.
PSVita.TV is relevant to Vita sales, however, since it can play Vita cartridges, and is relevant to looking at software sales, attach rates, etc., and since we come to this site to look at sales data, we should be able to see this.
I think the ideal solution would be tracking of the platforms broken down by model. A stacked bar graph which shows 2DS+3DS+3DSXL and any other models that may come, and another showing the Vita platform Vita+VitaSlim+Vita.TV. If this is possible it would be great. Otherwise I would probably track Vita.TV separately, as a home console. More questions like this may come up in the future, as I can see Nintendo doing wonky things with its next line of hardware, or further blurring of the PS4/Vita platforms.
