I would wait until the bugs are ironed out (around 6-12 months). There WILL be problems with the new units so jumping on them now is really only for those who don't mind dealing with Apple rev A products and the frustration. I learned a long time ago that it's not worth it and that if you have something that's working well and stable without issues, it's better to keep it until you are convinced that most of the issues with the new models have been fixed. If you don't use your MBP for work, then maybe it doesn't matter, but if you need your MBP I'd stay with the one you know is working. Reading discussion forums like Apple's own ones is a good way to gauge the situation. With regard to the yellow tint: we have no idea what displays they'll use. Judging from the past, they might even use the same displays as in the current crop.
Also, who knows, your computer's GPU might break and you might get lucky with Apple replacing the entire computer for you. Again, my experience is that often Apple repairs fix one thing and create something else and that there is always a good chance they'll mess up so much that they'll offer to replace instead. 🙂
