Seth wrote a post on designing web sites in which he says,
I'm going to go out on a limb and beg you not to create an original design. There are more than a billion pages on the web. Surely there's one that you can start with? If your organization can't find a website that you all agree can serve as a model, you need to stop right now and find a new job.
I agree. There is so much innovation happening out on the Web, why be an island unto yourself? Leverage what others have done but don't lift what others have done. Seth goes on to say,
Not a site to rip-off, but an inspiration. Fonts and colors and layout. The line spacing. The interactions. Why not? Your car isn't unique, and your house might not be either. If you've got a site that sells 42 kinds of wrapping paper, why not start by finding a successful site that sells... I don't know, shoes or yo-yo's... something that both appeals to your target audience and has been tested and tweaked and works. No, don't pick a competitor. That will get you busted. Pick a reasonably small but successful site in a totally different line of work. Say to your designer: "That's our starting point. Don't change any important design element without asking me first. Now, pull in our products, our logo and our company color scheme and let's take a look at it."
Here I agree that finding a functionally similar site, is a good way to find out which practices you should be embedding in your site design but disagree on things like utilizing fonts and colors. If you want to manage your brand, and ensure that every interaction that a customer or prospect has is with your companies' branded experience, then DON'T borrow from someone else's fonts and colors. Use what your team should be developing in terms of brand standards - fonts, color palette, imagery, layouts etc...
Seth made one more point which I picked up on...
The process of design and user interaction is best done separately from the process of server speed, database structure and uptime.
Hallelujah! One must separate out design from infrastructure. Infrastructure requirements should be developed based on the customer experience a company is trying to deploy NOT the other way around. I'd add one more point. User c0-creation! Do it! At the beginning of the design process and at every logical iteration of the design even post launch. Make your users an intrinsic part of the design process and team. You'll create a superior design in that way.