I was initially excited about the Nokia N97, simply because it combined a touchscreen interface with a physical keyboard, and the fact it was Nokia. However, Nokia's S60 over Symbian OS is not up to speed with today's hardware, and the reviews I read complained about the stoneage GUI and overall environment with the N97.
Enter the N900. Historically, the N7xx and N8xx series have been strictly Internet tablets, WiFi capable only, and based on Maemo, a Linux-based mobile OS. The N900 has changed completely from its last sibling, the N810. It adds GSM and HSPA functionality, the latest version of Maemo (Maemo 5), and Xvid-quality video capturing, geo tagging of photos, which is powered by a Carl Zeiss lens and dual LED flash, and applets that enable you to share all of this via social networks, such as Facebook, flickr, and Twitter.
The announcement came a few weeks ago that the phone will be arriving in US retail stores around the 27 of September. I am hoping that an announcement comes before it is released for sale that the unit is capable of 850/1900 MHz 3G (it only runs 900/1700/2100 right now, which is only supported by T-Mobile in the US ... blah!). That alone is the only deal breaker for me at this point. The price is very reasonable for a powerful Internet tablet that just happens to be capable of making a phone call. The processor speed, memory, and built-in storage are all equal to or slightly greater than that of the iPhone 3G S, and with the capability to expand the memory via microSD, the flexibility of the Linux-based OS, and the fact that this device comes from the world's leader in the cell phone industry, the apparent $600 price tag is worth it.