For this kind of work I would generally advise sharing the files both in AI (Adobe Illustrator) and PDF format...and possibly EPS. That would allow people to use whichever vector application they prefer.
Originally Posted by Herrie
I know Illustrator and personally think it's a bit cumbersome for these kinds of images...but that's my personal taste.
I've personally used CorelDraw for years now (just about all versions between 8 and the current 17). For vector graphics it's the environment I feel most comfortable in (although color-management is clearly worse than e.g. Illustrator). But I also know others who really, really hate it.
I've never used Inkscape, but I've heard great things about it, and it seems quite simple to use from what I've seen. Moreover, it's free and open-source, so everyone can use it. And that's a great plus to me.
That being said, I did take a look at one of Benjamin's images, and the way he uses Photoshop to create these icons is perfectly valid to keep the picture-integrity when resizing the image. There are some disadvantages to the images (e.g. in my PhotoShop CS3 exporting the image either to AI or PDF resulted in an empty page, and bringing it directly into my vector application resulted in a distorted bitmap), and I think that maintaining the images in a vector application is easier in the long term. But part of that is my personal taste/opinion, and I know others who disagree (and rightly so).
On a sidenote. A while back I looked at the webOS icons in the github repository, and decided to reproduce the memo-app icon. I've included the original memo-icon in the example, as well as the email-icon, since they have different background-circles (actually...the background circle of the email is used for the 64x64 version of the memo-icon). The top-gradient in my mail-icon is a bit too fuzzy on top (this is relatively easy to fix), but that was caused by me reproducing the 64x64 circle before I noticed that the mail-icon would be a better reference.
-- click image for a larger version --
It's not a 100% faithful reproduction, because that wasn't my goal at the time...but then again, I don't know if open webOS wants to be 100% faithful to the designs from 2009/2011 (and I'm not saying that the gray/flat eel/mochi look is what they should go for).