Mike is right - it's up to company policy and what you negotiate with the listing company. Certainly don't worry about offending anyone by asking!
Keep in mind that they would probably offer you a small discount as incentive to get you to list with them vs. another company, so make sure that you let them know that would sway you.
However, I wouldn't let that discounted amount determine who you hire. If you get a discount off the commission %, but end up with an unmotivated, inexperienced and/or incompetent company/agent, you would be better off hiring someone at a higher percentage, whose skill, marketing and determination will net you more in the long run.
To "save" 1% in commisson, only to have your home sit on the market for months and sell 15% under asking price (or be mis-priced to begin with, just so they can sell it quickly) wouldn't make much sense.
Don't let the commission % determine who you hire - interview at least 3 companies and find an agent who has at least 10 years experience or just started in the last 2 years (so they know how to market in a realistic market), who has good company support, who's personality meshes with your own (you should like them) and who has extensive knowledge of internet marketing. For instance, if your agent has never heard of Trulia or doesn't advertise listings here, they haven't a clue how to market a listing in 2009!
I would definitely recommend calling a Madison First Weber office, too (I'm in Milwaukee) and speak to an agent there. We have a great program called Front Runner that gives every listing syndication to sites like Trulia and Zillow, creates voice-narrated tours and has an awesome multimedia presentation that can be accessed by our Smart Sign text message technology - it's pretty cool!
I'm curious why you would want to do your own photos? Are you a photographer? Be careful there - what you may want to highlight in photos and what actually helps your house sell may be two different things. Just be sure they are clear, well-lit and there are a LOT of pics for the internet - that's where buyers decide if they will want to see your home or not. Photos are even more important now than ever before! Also consider video and flash tours, as well.
Good luck with your offer!