First, please let's be very clear. I'm not putting down your art here -- I think it's terrific! I can’t do stuff like this. But I can do advertising and what I am doing is bringing decades of advertising and marketing focus to the task of what an icon or logo has to do. It must be totally focused to be really effective. There are a lot of awful examples out there -- but the best really hit the spot in every way.

First, about the 32/64 aspect of PL. Only about half of Mac users switched to OS X.7.x -- the others (like me) are sticking with OS X.6.8 or lower mostly because it allows them to continue to use Rosetta so they can use legacy programs. And that demands that they work in 32 bit. So the fact that PL can switch between 32 and 64 bit is important. In fact, I have PL set to 32 bit most of the time so I can use several older plug-ins, and I switch to 32 bit + Rosetta when I desperately need to use one particular really old plug-in which I believe has not been matched/replaced by anyone and has not been updated since about 2002 -- Focus Magic.
In Windows, the position is similar. Vast numbers of people are still making life difficult for themselves on XP3. Do they run 64 bit? I don’t even know whether XP3 does 64 bit (I am clueless about Windows pretty much) but you can bet that lots of them do not. Again, the 32/64 bit switch is important.
From an advertising perspective, any logo or icon must be able to be seen and be clear in its message. This is important in respect of two things. The numbers you show in the icon and the lack of color.
As I said earlier, the numbers are not relevant to PhotoLine. The zoom starting point is 18mm -- common in full frame and even APS-C sensor size cameras. But these cameras are by no means universal -- far and away the great majority of people do not use such cameras or are familiar with the figures on the lenses so the figures have no significance for them. But they all are familiar with some figures on their lens which are relevant to the use of the lens. In this case, for PhotoLine, the figures 32 and 64 are both relevant to PhotoLine. People will recognize that if they see the icon in an advertisement such as in the "About" box you produced. A good ad! So I really, seriously, suggested replacing the 18-120mm with 32/64-bit or perhaps 32~64-BIT.
Again, from the advertising POV -- and this is what icons and logos are all about -- color and movement are to die for. In a still image, we can’t have actual movement but you, as an accomplished artists, have introduced latent or virtual movement by having your icon lens tilted off vertical/square. Nice work. All that remains is color. The context and size of display always have to be taken into account in a commercial situation, and in a widely distributed one, there is no accounting for how big or in what context a logo/icon might be seen. Even in your "About" example, where you have control of the color within the box which enables you to set it up so the black and silver shows to maximum advantage (and very nice it looks too), you still don't have full control of the environment because you don’t know what wallpaper people are seeing it against. With a print ad, you never know what other illustrations are on the page -- and even if you take a full page ad, you don’t know what will be on the facing page. You can be done big time by more vibrant surroundings.
The fact is, color -- bright color -- attracts our eyes first, last, and all the time! That's part of the human evolutionary advantage.
Here's what your PL icon looks like in my dock. It is a good icon at dock size, clean, simple, indicative of what PL is about, and very importantly, different. BUT whether it stands out well depends on the background. I run EarthDesk as my wallpaper -- a complete picture of the earth with satellite feed updates of clouds plus day/night (including moonlight) every 20 minutes. Magic! As you can see, your PL icon is pretty dull against the Atlantic ocean as it is right now in daylight compared with nearby icons, but as night advances, it will get duller. With a really dark night, it still shows, but on a moonlight night it practically disappears!

So I would suggest introducing at least a bright band (red?) on the lens -- perhaps the band where the zoom numbers are, bring the switch on the lower band around to the center and have 32 on the left of it and 64 on the right, reduce the width of the black band and increase the width of the silver band at the top to about the width of the wider band at the bottom, and put PhotoLine 32~ 64 BIT in that, but much bigger.
As for introducing the four color underline in the "About" screen, that looks nice but it ignores the fact that PL outputs in RGB as well -- and that every user will output in RGB for Internet use and only those who go to print -- a minority, probably -- will use CMYK. The fact that PL is switchable in that respect needs to be incorporated into an "About' screen or ads. It does not have to be incorporated into the icon since it already shows the dual nature of PL with its subject and the way it is drawn.
Adam, you can ignore all of what I’m saying of course. You have a graphic art perspective and you do it very well. I'm coming from a pragmatic advertising perspective -- as advertising manager and (low level) creative. I've commissioned and scores of logos and icons over the years, tested them, and introduced them. I'm long retired from the corporate stuff but still do advertising for small business along with photography and writing. That's the perspective I’m bringing to our discussion here.
For more information on that perspective, have a look at my ad site: http://www.ad-doctor-online.com. In particular, go to the "Get the Book" page to check out the free sample of my little book and the "Free Ad Tips" page for six more examples. Some of these ads are my own work, some are the work of others I've picked out of media to make a point - positive or negative.

Best regards
Geoffrey Heard
The Ad-Doctor-Online
http://www.ad-doctor-online.com