I'd go with the rectangular sink because it will, as you mentioned, have a bigger capacity than a D-shape. I have a large rectangular ss sink and sometimes, when I'm cooking a lot, it fills up quickly and I wish that I had 2... ;)

Yes, I know I could wash-as-I-cook, but I get behind...

Rectangle. For two reasons. 1. I believe they have larger capacity. 2. I have a wacky fondness for straight lines. Cleaner. Simpler.

Any faucet suggestions? Nothing too expensive but certainly reliable.

I don't care for D shaped sinks myself, but I believe you can get a larger D shaped sink into a cabinet than other shapes (remember the faucet--with a D you go to the side and the sink can go further back). You should ask this in the kitchens forum, where this has been thrashed out many times.

flynnnj--if you haven't been in to compare the sink sizes, I strongly suggest you do. 17" is quite narrow. You wouldn't think 1" is a big deal, but it is. Additionally, I think you can get a 23" (outside dimension)D-Sink in that base. That would give you 21 1/4" x 19" x 9" or 10" which is a bigger capacity than the rectangle will give you. Note that many sink & cabinet manufacturers will state you need 2" wider cabinet than the sink, but as we found out with our cabinet guy, that is typically a CYA move by the manufacturers--especially if you're using undermount.

Here's the link to the sink we used:
http://www.luxartcollection.com/ProdDetails.aspx?co=Luxart&Model=LXUS04

Overstock has some nice D-Shaped overmount sinks too:
http://www.overstock.com/Home-Garden/D-shaped-Top-Mount-Stainless-Steel-Single-Sink/6021755/product.html

Rectangular shape vote here! Faucets....the choices are endless! I have been researching faucets for the past couple of weeks and have decided on the Brizo line of faucets. They are made by Delta. Kohler fauctes, Danze are also good.
If you enjoy and have time for web searching, you can find great deals on just about anything for your kitchen! I scored the Brizo's (3) at great prices, but just about all can be found at discounts.

I have an Elkay 21 x 18 D sink. While its a little smaller than a rectangle sink, I haven't had issues with pots and pans not fitting. I went with the D bowl because the rear drain allowed for more usable room under the sink. My kitchen is small so the only space to fit my trash pullout was under the sink. With the plumbing in the back I can fit both the trash and a small can for recycling.

So many good suggestions and things to think about - Maybe the rectangle would be work best since it would be repeating the shape of the peninsula - but the D shape is a fresh new look.

I put a 32 oz. can of soup where a faucet would go. I tried it on the left and that didn't feel good to me. It looked good but made no sense since I'm right-handed. When I put it on the right that was fine but it really broke up the space on that side of the counter.

Most people will sit on the stools to the left or right of the sink - NOT right in front of it. When I pass plates across the counter it's usually to my right - I wouldn't want to bump into the faucet each time so it seems like the center of the sink will be best - similar to how it is now.

Can you place a center faucet into both shapes? Can a center faucet even work with a D shape sink?

>Can a center faucet even work with a D shape sink?

With a standard depth counter, usually the faucet for a D sink is off to one side. If your peninsula is deeper it could work, but consider whether the extra reach all the time would be comfortable.