Sony is laggish with firmware upgrades, so this is valid point to complain about, but check out our firmware
http://www.ebookapplications.com.
It installs by just copying file to the device's memory and loads as a optional boot, so you can choose during the device boot to load original firmware or alternative firmware.
It supports lot more ebook formats than original and has dictionaries support as well as better support for PDFs, custom fonts, flexible page-view settings. So check it out before making final decision and criticizing Sony devices.