Okay, I am getting back to Arduinos after a while, and I've programmed ATtiny's before, and I have used both High-Low Tech and Arduino-tiny and a smaller and even faster (claimed) library sometime back. Today when I checked, I found that there's been no development on Arduino-tiny since mid 2012, but HLT seems (perhaps) a bit more active. I'd be working mostly with the Attiny85's, I do have a good number of Attiny2313's which I could use. From what I understand, HLT doesn't support Attiny2313's, while Arduino-tiny does. Also, I remember some subtle differences between capabilities of the 2 approaches, with certain libraries working with one, but not the other - usage of Timer0 vs Timer1 etc.
If someone has the latest bearings on this, would appreciate if you could share the same, i.e. which one is recommended. I'd be using the timer and interrupts quite a bit, but need no PWM, and will be using only digital I/O for my list of projects.