I use WM 6.5.5 (23554) and HTC Sense 2.5.2012.1412
If you have problem, that describe ca3sar (see his screenshot), try corrected cab (People tab 4x4 WVGA sprint.cab):
22.4.2010 - test cab for VGA devices.
22.4.2010 - I have confirmed that, VGA version is working.
User AdamiX provide me his screenshots. Here they are.
22.4.2010 - I updated cabs with version, where facebook icon position is fixed.
23.4.2010 - If you get small icons, but in 3x3 layout try People tab 4x4 WVGA v2.cab