Here's my layman's understanding of the issues raised. Could be wrong and anyone's welcome to correct them.
1) why do some players have dual dacs? whats the advantage/disadvantage to players using only one dac.
The datastream retrieved from a CD consists of both left and right information plus a lot of error-correction and redundant data to make sure that the data is complete prior to waveform shaping in the conversion process. It is arguable if two DACs are better than one. But let me just say that I don't see any problem having dedicated DACs for each channel in the debatable interest to improve channel separation in the analog stages.
2) ive seen players touting 24-bit dacs (nad) yet some only 1-bit dac (some pioneer cdps ive seen) or am i comparing apples to oranges here. whats the difference? what advantage does a cdp having higher dac specs have over that with lower dac specs, 24 bit compared to 18 bit?
Entire books can be dedicated to this topic. The standard redbook CD is encoded in 16-bit regardless of which resolution was used in capturing the live performance.
Cd players start with 16-bit decoding and can upsample to 18-bit, 20-bit or 24-bit or even 32-bit prior to analg conversion. For me, this upsampling does nothing to improve upon the original performance, but does impart some discernible quality to the analog shaping that for some people. are superior to 16-bit.
OTH, 1-bit decoding exhibit some inherent noise that many audiophiles find objectionable. The algorthm decimates the 16-bit word lengths to generate single bitstream data and is buffered prior to analog conversion. This is the percursor of the DSD 1-bit resolution of SACD players, but, because the new technology does so at 2.83 Mhz, the resulting bitstream is said to be far superior than the 1-bit datastream used for CD decoding.
3) whats oversampling? is it the number of times the cdp reads the cd to make sure it read the cd right?
Yup. This technique (say, 8x the original sampling rate of 44.1Khz or 352.8Khz) is used to spread the quantization noise to a large set of samples often putting them totally outside of the Nyquist frequency limit of 22Khz. It also eases the anit-aliasing post-DAC filtering to make them work more smoothly
4) whats jitter? i used to think that jitter has got something to do with the motor of a cdp not being stable (sorry for my ignorance 
)
Again, an entire book can be dedicated to this topic.
This is the digital equivalent of wow and flutter in analog devices. It is a time-domain problem exhibited when the resolving DAC in not in synch with the arriving datastream so that it sees a 0 instead of a 1 or vice versa and shapes the analog waveform erroneously. Digital error in the time domain manifests as amplitude errors in the analog waveform with a net effect of raising the noise floor or decreasing the S/N ratio so that certain musical details and subtleties are masked or lost.
5) why are burr-brown dacs highly sought after?
I guess because Burr-Brown happens to be a pioneer in the industry with proven track in so far as hi-fi DACs are concerned. But that doesn't preclude other manufacturers from similar qualities like motorola, Cyrix, AKD, etc.
6) in many discussion groups ive seen, a lot of audio enthusiasts are saying that the most important part of the cdp is the power supply. i thought since cdps have relatively low power consumption (compared to amps and receivers), its power source shouldnt be a factor in the quality of its sound.
This is a design philosophy different brands adopt to come out with arguably better sounding CDPs. It has nothing to do with power delivered in the same way they do with power amps. I think having a cleaner power supply or dedicated power supplies for transport and electronics can make some difference in attaining the best S/N ratio and channel separation.
