Jim,

my experience was moving from pre-OS9 versions to OS9 and then on to OSX, and for me at least it was pretty bad, indeed. Granted, most of the apps that stopped working after that transition were Microsoft apps (what a surprise!) -- Foxpro 2.6/Mac being one of them -- but had I built my entire business on Mac at that point, I would have been out for the count.

Interesting tidbit about IBM. I remember writing Assembly on Series 360 using punch cards (not fun!). Have they kept their promise? What would happen if they didn't? Do people still remember, or is IBM waiting for a generation shift ;-)


Pertti


>I don't know about Apple's compatibility history, but I would be very (very very) surprised if it was as bad as you make it sound.
>
>MS had to retain as much compatibility as possible else they would have lost the game big time!
>
>Way way back when IBM announced a new series of systems (/360) to replace their current crop of 140x and 707x systems they made them totally incompatible with existing hardware. Even though their user base was small back then (relatively) they had a full-blown revolt on their hands and they finally had to promise - in writing and well publicized - thst they would NEVER DELIVER AN INCOMPATIBLE SYSTEM EVER AGAIN.
>
>cheers
>
>
>>>I appreciate it when they make a profit by offering me something I like, like Excel, a masterpiece of a product.
>>>
>>>A useful evolution is also welcome even if it is costly to implement, as was the evolution of Fox from 2.6 on towards 9. Note that old FoxPro code remained useable even if less than ideal.
>>>
>>>What I think is totally inconsiderate is to be forced to throw out old code just to play and then being squeezewd and pressured to change, as happened to VB as it went from 6.0 to VB.NET. The darn thing is I think they plan to do this over end over again. Planned obsolesence at its worst.
>>>
>>
>>Alejandro,
>>
>>I think over all MS has done a pretty good job with backward compatibility. VB was an exception more than anything -- they had to change it because of a poor foundation, while C code and its variants kept running just fine from one version to another. I think we are actually somewhat spoiled by MS's stubborn commitment to backward compatibility as much as possible.
>>
>>Years ago I tried to keep up with Apple's OS upgrades, but because of multiple incompatibility issues from one OS version to another, I finally gave up on native Mac apps and told people to get Windows emulators if they wanted to run my software. I lost a big chunk of my market right there, but it still made bottom-line business sense to me.
>>
>>The other side of the compatibility coin, of course, is the fact that by not being committed to 100% (heck, even 75% would have been nice) backward compatibility Apple has been able to create an extremely elegant and amazing user interface and a rock solid operating system, which IMO beats Windows coming and going.
>>
>>So, in a sense, backward compatibility is a major drag on technological innovation and advancement. While Apple has a fanatically devoted user base which for the most part stays with the company through thick and thin, Microsoft does not, which means that some of Vista's backward incompatibilities are starting to drive users away from Windows OS in droves. If Windows only was a bit hipper and more cutting edge visually and UI -wise AND if Bill Gates would wear black turtlenecks and don cool eye glasses AND get a hip haircut, Microsoft, too, might be able to stop spending a lot of money and energy trying to support the past without losing significant upgrade business.
>>
>>Pertti