Since you said "Macbook" (and not Macbook PRO), I assume that yours is the bottom-of-the-line model that came with a CoreDuo (not Core2Duo) CPU. If that is the case, then the reason you got dropped off the upgrade chain is simple: Your CPU does not run 64-bit code. I'm not an Apple dev.; but I'm pretty sure that Mountain Lion represents Apple's move to a "64-bit clean" architecture. This is overall a good thing.
Funny that I got two responses along these lines. It is, in fact, a Core 2 Duo white Macbook model A1181. 10.8 doesn't support it because Apple decided to delete the X3100 video driver, not because of any defensible technical justification.
Note that people have gotten 10.8 running on machines of this vintage by copying the 10.7 X3100 driver bundle unmodified into their 10.8 installation. Why doesn't Apple just do that? Because they want to sell me a new Mac. I refuse to go along.
You just got caught out by an architecture-shift. Happens.
That's my point. It happens if you are a Mac user. Windows and Linux users do not have their operating systems vendors arbitrarily decide that five-year-old hardware is obsolete. I don't think it's a coincidence that in this case the OS vendor is also the one trying to sell me new hardware.
And just because Apple doesn't regularly issue updates back more than one "major version" or OS X, doesn't mean it NEVER does. In fact, I believe that Apple just released a security update for OS X 10.5 about a week or so ago.
Yes, it was a security update that disables old versions of Flash. Aside from that, there hasn't been a single security update for Leopard since Lion was released.
There are a gajillion Windows PCs in service right now that can't be upgraded past XP. So what?
I can guarantee you that not one of those is a five year old Core 2 Duo laptop sold by a major PC manufacturer.
The G5 tower I purchased about a MONTH before the Intel-Switch was announced can't be upgraded past OS X 10.5 Leopard. But ya know what? That G5 tower just happens to be my main computer, and is the one I am typing this post on.
I'm glad that works for you. But again, if you look at the history of Apple's security updates, you can't trust them to keep old versions updated. This is not a problem with Windows or Linux. Besides, quite frankly I don't like the idea of being stuck with old software. Personally I've always been a very early adopter -- I ran alphas of Mac OS 8 when it was called OS 7.7, and OS X when it was called Rhapsody. (No, never tried to run Copland -- not *that* crazy
So, by the same token, the Windows PC world should be chastised for putting out machines that can't be upgraded past their ORIGINAL OS (let alone a couple of major revs forward!)? And that some of those laptops were purchased within a year of XP no longer being loaded by OEMs? And how about all those Windows machines that were NEVER capable of running some of the VERSIONS of the SAME OS? At a former employer, they purchased an HP laptop for a salesperson that couldn't even LOAD XP Pro, and therefore couldn't log on to our Domain. That's what I call INSTANT obsolescence!!!
Sounds like driver issues. If that happened to me, I would definitely avoid the manufacturer of the product that was preventing the upgrade. Which is exactly what I've been saying -- you just don't like it because the manufacturer I'm talking about is Apple.
The problem stems mostly from the fact that Apple is holding on to the "10" part of the OS X name for too long; making people think that each major revision of OS X is "just a simple upgrade"; when there are deeply-rooted (no pun) changes happening under the hood.
Not sure what that has to do with anything. I know what the differences between 10.7 and 10.8 are, and I know that none of them justify what Apple is doing.
You are essentially whining that your Windows XP laptop won't run Windows 7. Do you really think that will cease if you "jump ship" away from OS X???
No, I am aware that (particularly in the Windows XP -> Vista transition) there were quite a hardware manufacturers that were slow to make the transition. But XP continues to get security updates, and 10.5 (soon to be 10.6) does not.