“Working with the other compatibility sites should not pose too big a problem I guess.”
I was not even really thinking of working with them, unless of course they want to, but rather just linking to them for more information. The only compatibility-related data I was thinking of having “on” the site was a yes, no, or maybe rating.

“Create a standardised web-form reflecting the structure of the database that can be filled and updated wiki-style.
Perhaps even vendors will contribute.”
That is exactly what I was thinking. I don’t know exactly how to implement it, but wiki-style is definitely the right approach.

“I’m thinking of the many price guides that offer some kind of standardised input forms for their advertisers. They usually offer exactly the kind of search facility you are describing. The data is kept up-to-date by the vendors out of self-interest.”
1. Yeah. Places like pricegrabber do exactely what I am thinking of, except for the Linux compatibility part…
2. You made me realise that pricing data might be able to be retrieved from a site like pricegrabber. Based on the number of sites that use data from those places I expect that they provide an easy way to include their data in your site.

Getting a steady stream of up-to-date data:
Create a standardised web-form reflecting the structure of the database that can be filled and updated wiki-style.
Perhaps even vendors will contribute.

I’m thinking of the many price guides that offer some kind of standardised input forms for their advertisers.
They usually offer exactly the kind of search facility you are describing. The data is kept up-to-date by the vendors out of self-interest.