My further upgrade path has been thus:
The AWS version was compatible with both Rogers and the "new" providers, WIND and Mobilicity.
It was massively better provisioned for memory and CPU than the Dream. Unfortunately, it proved prohibitively troublesome to get it to run CyanogenMod, as the built-in firmware is quite uncooperative with the requirement to replace said built-in software. When the screen began misbehaving, I was not appalled at the thought of upgrading to a new phone.
Samsung Nexus S
Slightly small of screen, but mighty nice.
Samsung Galaxy Nexus
Upon switching to WIND Mobile, I updated to the new "flagship" Nexus phone.
CyanogenMod is a free, community built distribution of Android which greatly extends the capabilities of relevant phones. This includes both minor and fairly major "tweaks" and extensions to the software built into the platform, substantial efforts on performance optimization (so that it has worked fairly well, even on an ancient HTC G1), and inclusion of interesting free software into an overall software distribution (not unlike the way the Linux kernel is assembled, along with a cast of supporting software, into a Linux distribution.
I'm taking a look at Android-based tablets to provide something bigger than a phone and more portable than a laptop
Not useful, but entertaining; let your phone display what looks like the DOS Boot display.
I don't agree with all the choices, but there are a lot of interesting apps listed here.
Some Android devices are easy to customize to run your own firmware. Others, not so much. (My HTC Legend turned out to be in the "not so much" category, sadly.)
This project has the purpose of letting you run a chrooted Linux distribution on your Android device. It works on a number of rooted devices, and if you have a portable device that can connect to a large screen (generally via HDMI, these days), this could give you some of the best bits of several worlds, namely a tremendously portable device that still has a huge screen and keyboard and such.
A somewhat peculiar thing about the newer "PDA" platforms is that the built-in capabilities for note-taking are rather limited. This contrasts, for instance, with the Section 2 platform where "Notes" were a basic built-in feature.
Some interesting web services have emerged.
This is, in practice, what I generally use for notes.