Or in other words, how do you develop your application so you can easily pick up the next big thing?
Do you dive deep into the current technology, like Java, C#/.Net, … and ignore the future?
Or are you using slightly older but proven technologies like C++ and already struggling on how to move to newer technologies?
Or have you found the perfect solution and already mixing different technologies (C/C++, COM/ActiveX, .Net, …)? If you did, did you encounter performance or maintenance problems?
Is it OK to mix technologies everywhere in the code or do you have to define clear boundaries?
It seems to me that transitioning from one generation of languages to the next is getting easier with each iteration. CGI scripts were capable of working side by side with practically all of the server side scripting languages that popped up and those that jumped onboard with OO driven web development could still use their existing binary libraries through some clever techniques. I dove pretty deeply into ASP Classic even developing COM components that I would port around to different sites. I was able to first run ASP Classic and ASP.Net pages side by side, then I moved to having the ASP.Net pages call my existing COM libraries and then moving on to replacing the COM libraries with .Net equivalents. I never felt any pressure from the industry to do it but the clear advantages to the newer technologies were all the encouragement I needed to spend the extra time to convert everything over.
All of this is pretty irrelevant however. If the next generation of development technologies leaves your current work out in the cold there’s really nothing you can do about it. They aren’t here yet and you need to complete your projects. Ultimately the only thing you can do is write structured readable code so at the very worst you’ll at least be able to understand what you were doing so you can hand copy it later.