re: Proposal for landing site of the Phoenix Mars lander.
The landing regions for Phoenix under consideration are shown in the image below, taken from Fig. 1 of the report:
OVERVIEW OF MARS EXPLORATION PROGRAM 2007 PHOENIX MISSION LANDING SITE SELECTION.
Seventh International Conference on Mars.
http://www.lpi.usra.edu/meetings/7thmars2007/pdf/3204.pdf
Region D currently is the leading location for the landing.
Bob Clark
Figure 1. Polar perspective view of MOLA topography
with Regions A, B, C, and D shown. Each Region
covers the latitude range from 65° to 72° N. Region A
covers 250° to 270°, B 120° to 140°, C 65° to 85°, and
D 230° to 250° E.