When it gets to the point where it becomes too much work to support 2 engines we will see BI go away, but I think by then most hardware will be up to cycles level anyway. I’m curious about how much difference there is in BI and cycles when it comes to things like bmesh and particles, can BI actually handle drastic changes easily?
I solidly agree, I know almost nothing of Cycles and I’m not sure I want to change. For those of us with only laptops (like me) good GPUs are hard to install and that’s what Cycles relies on. Also, the whole realtime render option wasn’t available in 2.61. So long as you know the right techniques BI is just as capable as Cycles.
I really don’t hate cycles, and I’m actually trying to learn it. I just don’t believe that it’s a good idea to take out the BI in favor of cycles, I think keeping both would be best, especially if they could work together.
But this thread convinced me that there is still time and it’s too eraly to have this debate.
I will always keep either BI or Yafaray as alternatives because there are things that they are just better at. Cycles is nice, but there is also Lux and SmallLux GPU. Personally, I’m not ready to use something like Cycles in animation, since I have to find the magic samples number, while it seems I’m better off in BI or Yafa using a “point and shoot method” that get developed over time. You get a feel for a bucket renderer which I have not found with Cycles. I am in no way down playing Cycles, but in some cases I find other rendering options faster and more predictable than a progressive path tracer, and while Cycles is fast at rendering in some cases, it also feels like a step back in others. I like shiny new things, but I have to admit, I’m not that into it right now like I would like to be.
Personally I hope they’ll keep the Blender Internal render engine at some point. Because these days you need a fair good pc to render something. For example 3ds Max you need already 2gb to create something at all. The good part I think about blender is that it gives 3d graphics creation to anyone who wants to. An old single core pc can still run this software and make people able to learn 3d modelling.
For me as example. I had my first pc which was a compact 468, and thanks to blender I was able to use a 3d application on this machine, while any other 3d application just didn’t run at all without a graphics card. Because my parents didn’t had the amount of money to buy me a new pc, I could still step into the world of 3d.
I hope they keep the BI, just to give those people that aren’t able to spend money on gpu’s that are needed to render anything worth with cycles. Blender is opensource to give everyone an opetunity to improve it, but also to meet the world of 3d graphics. It should stay that way.
However if they manage to let cycles do what BI can do at same other better speed but besides that also has the option to use the GPU to speed it even more. Then I would say, why not. Until then, just include BI to bridge the gap there is now between BI and cycles to let every person enjoy the fun of 3d graphics. 
While I use commercial 3d software at work, I still have respect for blender. It’s lightweight, runs on really budget machines and has incredible tools that even proffesional software just misses. One thing compared to ex: 3ds Max, blender is just incredible stable. Afther a few years I decided to pick up Blender because of this, to play around at home and even find a possibility to setup a commercial pipeline at home for 3d graphics. Even when I stopped, I love blender 
BMesh was trivial to update with both Cycles and BI - there were/are many other issues but they are unrelated to rendering. - Mainly because ngons are triangulated before both cycles or BI touch them.
btw, I wouldn’t worry of BI being removed until cycles well and truely replaces it in almost every way.
Also, if there really is a place for BI - it may stay maintained - or a replacement be re-written as an extension.
Cycles doesn’t rely on a good GPU, it renders just fine on a laptop CPU.
Also, the whole realtime render option wasn’t available in 2.61.
I don’t know what you mean here. Viewport rendering has been part of Cycles in 2.61.
So long as you know the right techniques BI is just as capable as Cycles.
Since you admit to know “almost nothing” about cycles I suggest you reassess whether you are really in the position to make that claim.
The old releases aren’t going away, they will always be available. There’s no point in supporting old hardware though, if that means hindering progress.
Also, Cycles is not really slower than BI at a comparable quality level. If you turn on glossy reflections, environment lighting, ambient occlusion and indirect lighting with BI, it will likely take longer to render.
We should focus on getting the best render solution as good as it can get, before trying to maintain several render solutions.
And outdated and underpowered hardware shouldn’t have any priority.
3D rendering can’t be done on a microwave, a toaster or an MSX or Atari computer.
And this is fine, development should focus on hardware of the (nearby) future not of the past…
Once the best render solution is fully functional and operational, then other renders should get attention.
For old and outdated support, use old and outdated versions?
You simply can’t support it all (unless there is someone feeling the need to this all)
What more important is then supporting low-end hardware:
stay clear from proprietary solutions, no dependencies on none-open standards.
i’ve downloaded the latest SVN where can i find Blender Internal programming code
Blender Internal will not die completely, although it will become a collector’s item, like Elvis memorabilia.
“source/blender/render”