I don't have personal experience with 96K, however, I've not heard anyone talking about something as simple as that making an "incredible" difference.
So, the answer to your question is, no, don't sell your receiver. Wait till the High Def DVD war is over, and if either format survives, then get a high def DVD player because there are new audio formats that will make a clear difference. The dust should be settled in about a year, at which time you should also be able to get a receiver with HDMI 1.3.
Rest easy

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