After installing the latest 1.23.4.123523 RC viewer, I noticed on startup I no longer received the "Your graphics card is incompatible with Second Life" message. Knowing full well my laptop graphic card, is in fact, not compatible with SL, I wondered why this message did not appear. Instead I received the "Your settings have been changed according to your computer configuration" that I guess people with normal computers receive upon installing a new client. So I opened up my preferences to change to my usual settings from the default "Low" and I noticed the 'Avatar Impostors' feature had been greyed out. I had always been able to use the 'avatar impostors' feature before, on the same bad graphic card. I was under the impression it was a part of the default "Low" configuration as a performance enhancer on laggy situations and low end computers. I have enclosed the screentshot of the greyed out Preferences screen in 1.23.4.123523 as well as a screenshot of my usual Preferences screen from an third party viewer with the Avatar Impostors feature turned on.