How many channels?

I'm just starting to bridge the gap from 2 channel to HT and have a few questions. If I want to build a system, should I put together a 7.1 channel system? How many DVD's/SACD's/DVD-A's offer 7.1? Is the market headed to 7.1?
Just for the record. If the use of the word "gap" implies that multi-channel is somehow out there in front, well....

If you like movies HT/multichannel is the way to go. But there are a lot of folks, such as myself, who believe that there is no "gap" between 2 channel and HT. They are just different things. For my ears, if you are spending less than what would cost to build a small house, 2 channel (2 speaker)is still the place to be. I have heard some nice subwoofers systems too. 95% of the surround sound/HT systems that I hear (again my ear - admittedly I ran out of Q tips years ago) are not up to playing music.

And who cares where the market is headed - its driven by geeky vice presidents who want to take your money. Use a different standard to build your system. They change direction every few years just so you think you have to buy new!

Good listening
Hi, Craig:

Please bear in mind that my answer to your question reflects one man's opinion, and that I have some biases when it comes to home theater (in my system, top quality audio is the priority, with HT a pleasant but clear second...).

My short answer is: if you are just starting on your HT system, stick with 5.1. I say this for a number of reasons:
1. The "newer" formats of 6.1, 7.1, and 10.2 are still in their infancy, and it's very questionable that they will ever become a strong factor in the HT market.
2. The more channels of amplification that you add, the greater the initial expense. You're MUCH better served to spend your money on a good quality 5.1 channel system, rather than a mediocre quality 6.1, 7.1, etc. After you assemble a really good 5.1 channel system, you can upgrade at a later date (if that seems like a good idea at some future point).
3. There is virtually no software on the market yet for the newer, additional channel systems. 99% of the DVD's available are 5.1 channel (or less).
4. There is a reasonable liklihood that the current DVD format will be replaced in the next 5 years by FMD (fluorescent multilayer disk), which has the capability for storing much more data than DVD, and is therefore suitable for the high definition TV's that are becoming more affordable. FMD may or may not have more than 5.1 channels, but it will certainly be targeted initially at the vast majority of people who own 5.1 channel systems.
5. Last, most home users don't really have a home listening environment that requires more than 5.1 channels. If your audio/HT room is of average size, you will have enough challenge just getting 5.1 channels optimized for the best sound quality, let alone worrying about have another pair or two of speakers to place and try to balance to achieve coherent sound.

I'll repeat my basic message should it have gotten muddied:
spend as much as you can afford on building a high-quality 5.1 channel system first. You'll get a lot more enjoyment from your investment.
Thanks Sdcampbell for your great response. Music reproduction will be the most important thing my "entertainment" system will do also. My one system will have to reproduce music faithfully for my ears yet entertain my family and friends with movies, televison and video games (XBox). I will put the time and money into doing it right.