Oh, okay, I get what you're saying. I may not see the need for a 5" tablet for my car, but someone might. Dell has the luxury of spending millions to develop the Streak even if the target audience may not be as large as a 7" tablet, but that need exists and Dell has an answer for it.
Speaking of needs, any tablet I'd buy would need Exchange e-mail support baked in. While I'm perfectly fine with a touch keyboard, I'm curious if any of the new tablets would come with a "full-size" slider keyboard? If I'm doing serious typing for anything more than a couple of e-mails back and forth, a real keyboard would be nice. Likewise, the ability to display Word and Excel documents is important; editing them would be an added bonus. Synching documents/media/contacts to and from my desktop is a must. I'd like to be able to upload photos from my digital camera into the tablet so I can not worry about filling up the camera's memory card.
I need a VPN tunneling system that's compatible with our corporate system so I can remote in to provide support while on the road. Wi-Fi is essential; 3G would be nice, but a miniPCI (or whatever the PCcard standard is for portable peripherals) slot so I could choice my cellular provider with a card or dongle would work. I'd like at least two USB ports for connecting external storage and peripherals, mini-Display Port/DVI/HDMI out that mirrors the main display and can act as a second display for presentations, and combo analog/TOSlink 3.5mm input/output jacks for supplementing the built-in stereo speakers. And battery life that allows me to use the tablet while en-route without scrambling for an outlet when the plane lands.
The touch screen would be capacitive or equivalent as I've used both resistive and capacitive screens and resistive screens are designed to slow down user input which makes them great for automotive use (fewer false presses), but not what a tablet should use. The touch interface must respond without hesitation to maintain the concept of interacting with the "real" data under the glass. As I move my finger across the surface of the tablet, the item underneath must move with it immediately, not after a tenth of a second. Also, support for a pen or stylus of some sort would be great, as I don't draw with my fingers (not since elementary school).
Given all of those requirements, I don't have a tablet device at this time. With the timing of my AT&T contract on my old Motorola RAZR, I got the iPhone 4 as the Aria was the only Android phone that AT&T had at that time and I didn't like the screen size. Having the iPhone has taken a lot of pressure off of me getting a tablet at this time. It will be interesting to see how the market looks in 18 months after all the Honeycomb and Chrome tablets are out. Maybe Microsoft will be able to produce a competent tablet OS (I've used XP in tablet form and I choked on it. Maybe 7 is better.) and will be a player. And HP is a dark horse with WebOS. From the demos of the new version, it looks pretty snappy and I know HP makes excellent hardware, so the 8" Slate running WebOS might be the ticket.