R61 or T61? Same configuration and different prices

Hi everybody.
I found these two machines with same configuration
and different prices. Which one should I buy? What's the
difference between R61 and T61?:

T61
Intel Core 2 Duo processor T8100 (2.1GHz 800MHz 3MBL2) Genuine Windows XP Professional 14.1 SXGA+ TFT Intel GMA X3100 GM965 2 GB PC2-5300 DDR2 SDRAM 667MHz SODIMM Memory (1 DIMM) UltraNav (TrackPoint and TouchPad) 160GB Hard Disk Drive, 5400rpm DVD Recordable 8x Max Dual Layer, Ultrabay Slim Intel PRO/Wireless 3945ABG Integrated Bluetooth PAN 6 cell Li-Ion Battery 8897: Express - 1 Yr Depot Warranty + 3 year depot 9x5 Next Business Day.
Total cost: 952.34

R61
Intel Core 2 Duo processor T8100 (2.1GHz 800MHz 3MBL2) Genuine Windows XP Professional 14.1 WXGA TFT Intel GMA X3100 GM965 w/ 1394 2 GB PC2-5300 DDR2 SDRAM 667MHz SODIMM Memory (1 DIMM) UltraNav (TrackPoint and TouchPad) 160GB Hard Disk Drive, 5400rpm DVD Recordable 8x Max Dual Layer, Ultrabay Enhanced Intel PRO/Wireless 3945ABG Integrated Bluetooth PAN 6 cell Li-Ion Battery 7732: 1 Year Depot Warranty – Express + 3 year depot 9x5 Next Business Day.
TOTAL cost: 836.09

Thanks!

 

T61 has 4:3 1400x1050 display (=SXGA+). Standard-aspect ratio (better for almost everything except watching widescreen movies), higher resolution (more screen space), but at the cost of everything being pretty small (some people don't like it so tiny).
R61 has 16:10 1280x800 display (=WXGA). Wide aspect ratio, you'll have to scroll vertically more and tend to have unused space on sides, nevertheless your widescreen movie will fill in almost whole screen. Lower resolution overally, so less screen space, but everything will be slightly bigger.

Plus R61 is a little bit thicker, probably weighs a little bit more and I think its Ultrabay is 12mm high instead of 9mm (T61), so it can acommodate Blu-ray writer.
T-series used to be flagship product, whereas R-series were budget, but the differences very much diminished.

 

.....T61's have the option of widescreen 14.1" or 15.4" displays as well.

Also, the T-series has a mobile workstation variant (the T61p) with a more powerful graphics card. Otherwise, it is just a bit thinner, and has a 9.5mm slim optical drive.