Hey now! I still have over 600 LaserDiscs and a couple of players.
But I remember failings like Sony's Elcaset tape unit, EISA computer bus, "Super disc", and at one time, Sony even had a 3" diskette drive, which lost to 3 1/2".
The reason developers won't flock to Entourage devices, besides all the reasons presented already, is that other platforms are much easier to hack. There are tablets out there that have "roms" (firmware) aplenty.
Let's try to get the most from our devices, but not obsess over them. I'm confident that, WAY before the battery in my eDGe fails, there will be better, faster, lighter tablets out there that will make the next transition worthwhile. Then my eDGe will become a (wall-tethered) night stand browser, alarm clock or photo frame!