I do NOT want to start a fight with you, Coding Badly, but with the help of my tutorial on instructables you can program many AVR MCUs.
There are other core files out there other than the ones from Coding Badly and Mark Sproul (witch are used in my instructable), so choose the ones you think are the best.
I use Mark's because they have support for many different MCUs, not only ATtinys.
@alah did not ask about "many AVR MCUs". He asked a specific question about two specific tiny processors.
If you had taken the few seconds necessary to follow the link I posted you would have found that the opening page of the website includes a list of cores appropriate for tiny processors including Mark Sproul's core.
His core is incomplete for tiny processors. There are much better choices available.