As a Linux user, I've already resigned myself to a pocket computer landscape dominated by other OSs. The problem that Maemo and other Linux mobile OSs are up against (and no, I do not consider Android a true Linux OS, kernel notwithstanding) is twofold:

1) Telecoms want control over software -- they want to be able to limit features, lock down phones, etc. Both Android and iPhone OS offer that.

2) For the average user, the primary appeal of software is social, not technological. Most people could care less about how hackable or flexible their device/OS is. They just want the apps and features that their friends and coworkers use. This is also true with enterprise computing. Momentum and compatability are everything. Hence, the longstanding dominance of MS Office in the workplace, despite its technological inferiority and expense.