I have to admit, I switched to Google Reader a couple of years ago, but I do think the demise of Bloglines should be lamented. I found it incredibly useful when I did use it, and I can't actually quite remember why I switched anyway. I do remember it being fairly easy to export all of my RSS feeds, so hopefully anyone having to make the switch now won't find it too onerous.
It appears RSS feeds are on the way out, but why? Twitter is fine, but:
1. I had to get special dispensation to be allowed to use it at work.
2. It's a bit of a jumble with professional/personal crossover, and I don't want to deal with more than one account.
3. Sometimes it just moves too damn quickly! I'm not permanently plugged into it, I have other things to do.
I like the option to dip into my RSS feeds two or three times a week and find everything there, just waiting for me (I also really liked being able to publish useful stuff on my own Bloglines blog, but I didn't think anyone else was looking, so wondered what the point was). I've built up my RSS feeds over time, and don't know where else I would be able to find that wealth of information just waiting for me to read it when I'm ready. The Krafty Librarian agrees.
Google Reader does a decent enough job for me to keep up with all of my feeds in one place, although as the Health Informaticist points out, it has an annoying habit of asking me to upgrade my locked-down, NHS-issue IE6 browser on a regular basis. I'd love to dear, but I can't!