I don't know what the plans and timing for arduino-0008 are, but I've made some observations about the base software (targets/arduino and targets/libraries) and think they can be improved upon. From reading the disassembled code and measuring the time of various operations I can suggest at least the following: - Make pin data stay in flash, saves 130 or so bytes of SRAM. - Recode pin data access functions, digitalRead and digitalWrite, saves ~400 bytes of flash, digitalWrite() is nearly three times as fast. - Make delayMicroseconds and pulseIn be independent of CPU clock rate. - Fixup SoftwareSerial to be clock rate independent and generally better timed. You can now expect it to print without any garbage characters coming out. - Expose the useful bit of API for people that need to get port and bitmasks for sub-microsecond accuracy on their digital IO. - Fix delay() so it really will delay about 1ms if you do a delay 1. It could come back much sooner than you expect now.
The danger in this is that code which works under 0007 might stop under 0008 as the underlying functions get faster. People's hand crafted fudge factors would need to change. Also, there are other gains to be had that might have a minor change in semantics, such as requiring people to call pinMode() when they want to return a pin to digital use after having been used as an analog output.
On the other hand a fair bit of the help requests on the forum are for people with timing problems and people that are probably running out their SRAM and tightening up the cpu use of IO functions and RAM use could keep more of them out of trouble in the first place. (Also I was planning to make and study a native USB interfaced Arduino and had to get down to 12MHz which started me down this path. I suspect the USB requirements will be too limiting of what else can be done, but I'll see.)