When the PSR 900 was first announced, I was waiting for it to be released because I really liked the PSR800 I had as a loaner from a friend. Then of course, GRE America went paws up.
Now, it's what, two years later? The Whistler version is about to be released, but it's already almost outdated. I wouldn't expect any totally new Whistler designs for two years and would be surprised if one came out before then. It could happen, but the finances don't seem to make sense.
As to MotoTrbo it's not open source, but I believe DMR is an open standard and that the Motorola features could be reverse engineered without copyright infringement. Remember that the original Motorola and EDACS systems were proprietary and dedicated hobbyists reverse engineered them.
At least that's my non lawyer and non software engineer opinion. After all, a number of companies managed to duplicate the IBM PC without running afoul of their lawyers.
Time will tell.