November 2009 UpDate:
I saw this old thread in passing and thought I could offer an updated progress report.
I wound up "buying" the Shopp plugin (vs. the WP-ecommerce). My decision was mostly based on the level of support I could see in evidence on the plugins' respective forums. While WP e-commerce was "free" they did not seem to have enough people on staff interested in helping users.
Selling things online is definitely the way to go -- interactive and fun -- you can have casual, up close and personal relationships with your customers.
BUT, when it comes time for money to change hands you cannot afford to be casual. There are
laws, your livelihood, the trust of financial institutions
AND the trust (AND funds!!) of your customers all very much at stake. If your site collapses in the middle of processing someone's Mastercard you're done for. There's already a large group of people who won't consider using their credit cards on the web. When a person at your website types in their ccard account number, clicks
submit and gets a "404 error", you're done. They'll want to know exactly what
YOU did with their
sensitive info.
...and if you go to your ecommerce software's support forum and ask for help, and there's no response for
WEEKS, what use is that?
At that point your state's attorney general probably has a task force investigating your tax returns for the past 10 years!
So far so good with Shopp. There's a small "jquery conflict" (double library calls) with Atahualpa that seems like it might slow things down a little. It's easily fixed/avoided by removing a line of code so there's only one jquery library being brought it. (note: I don't really understand what I just said -- am just parroting what I've seen smart people like Shopp Forum admins, Flynn and Juggledad say in posts)
I'll try to remember to come back here periodically with fresh news.
Jim
PS -- I can't see why there appears to so little interest in the "Atahualpa and e-commerce" subject. Am I like the only person who finds this complex and a little bit scary? I tried to interest Flynn in setting up an e-commerce thread here in the Forum, but he pointed out, correctly, that not many people seemed to want to talk about it.