I just got my first BlackBerry last week - a Tour 9630 for Sprint. I love it!
I had a Palm Pre that I liked a lot, but it just had too many problems all the time (hardware AND software). I've always heard BlackBerries are super reliable, so when a really good deal came along for a used Tour I jumped on it.
Before I got it, I was concerned about switching from a touch screen to a trackball. It hasn't been an issue though, and I see myself sticking with this phone for a long time!
I am on Verizon and, at the time, my only "new" choices were 8130 Pearl or World Edition, so I got the Pearl and loved it, except for the small screen!
A 8130 Pearl on Telus. I came from the world of Motorola clamshells (previously had a 8707 Timeport, V60c, V710, Razr V3c, and Razr V9m...even used an i580 for work ) but got sick of the lack of features and innovation, so I decided it was time to make the jump to a smartphone. Telus was offering the $15 unlimited data plan at the time. I was looking for something with good RF and a relatively small size, so the 8130 was the perfect device at the time.