Yep after the 12b37 update I noticed my shifting got worse until the point that my clutches were just recently replaced due to a TSB that involves a leaky seal somewhere in either the transmission or the engine. Either way I had a lot of Noise from my tranny, Inconsistent acceleartion (like surging), RPM's would flare up and hang at various places on the tach and acceleration would lag.
After the new clutches. It is a whole different car. The acceleration is always consistent, passing gear and downshifts are snappy and hold through the expected shift points and redline and no weird noise or shudders.
I do though still get early upshifts when making 90 degree left or right turns though.
2012 FF Ti HB Platinum White Tricoat, Built 12/11, 401A + Parking Technology Package and MFT w/NAV at 3.5.1