Perhaps the DACs in your 3910 are better than what is in your receiver. That seems strange though seeing that your receiver supports Denon Link, you would think it would have excellent decoding and DACs. Did your receiver come with the Denon Link cable, or did you buy a separate cable?
If you get a PS3 you won't get the full advantage of HDMI 1.3 with an HDMI 1.3 receiver. The hardware in the PS3 doesn't allow bitstreaming of the HD audio (which doesn't really matter unless you want to be decoding DTS-HD). Hopefully in the future they will have a firmware upgrade that addresses the DTS-HD decoding. An HDMI 1.2 receiver or pre/pro could do basically everything an HDMI 1.3 receiver could do when connected to the PS3 in terms of audio decoding.
Speakerman, I agree, the Pioneer VSX-1018 does look tempting. It's a significantly more powerful receiver. If it sticks to tradition it will be THX certified and feature a 650 VA power supply with a hearty output section. It will also exhibit a wealthy bank of inputs as well as preouts.