There are some indications that yes, indeed, Linux netbooks may have to fear Apple Netbooks. They should. While I’m bullish on the opportunity for netbooks that are based on Linux, that is based partly on the fact that Linux faces really only one competitor, which is actually a ‘retired’ OS (Windows XP). An Apple netbook with iPhone-like connectivity and touch functionality would be formidable.

However, I again think that the biggest opportunity for netbooks, which are a primary driver of PC shipment growth according to IDC, is for ones that are based on Linux. I’ve already talked about the flexibility and development advantages of an open platform. Still, as is often the case with open source software in the end, it’s about cost. The reason Intel is investing heavily in Linux for mobile Internet devices and emerging mobile form factors (like netbooks) is largely because of its lower cost. Linux also offers greater ability for device manufacturers and others to add on their own brands and features.

I was recently asked which netbook I would choose given a choice between one based on Windows XP or one based on Linux. Given my experience with both, I would feel more comfortable with the Linux version. This is not only because of a personal preference. There are several concrete reasons why Linux makes more sense, not only to manufacturers and vendors, but actually to users.

First, if you compare Linux-based versus Windows XP-based netbooks in today’s market, you typically find that the Windows XP models, while they may even be priced slightly less than Linux versions in some cases, come with smaller hard drives or worse, hard-disc drives. If I want a more mobile computer that I can carry around like a cell phone, I want solid-state storage. My experience so far is that the Linux version affords the manufacturers and sellers to spend and offer more on memory and storage. The second reason I believe Linux is better suited to netbooks than proprietary systems, including Mac OS X, is that it comes with the typical Linux distribution selection of free software, including everything from email to backup to games. A third reason — wherein Linux has a definite netbook edge over Windows XP, but definite competition with Mac OS X should Apple jump in — is the maturity, development and advancement of the OS. Linux and Mac OS X are moving, Windows XP is not (even though many are using it in place of Vista).

So what happens to the Linux netbook opportunity if Apple enters. Well, I would echo Xandros CEO Andy Typaldos, whose company’s OS is in the popular Asus EeePC. He says the entry of Windows XP here shows how significant the opportunity is. I would say the same for an Apple entrant. Either way, the Linux netbooks — which are currently out catching the attention of conference attendees, college students and coffee drinkers — are still likely to have a significant price advantage over Apple, one that seems ever more significant given economic conditions.