Say that Metro Rail ever reaches as far west as Westwood Village. It's going to need a station, and Metro says that station would open as one of the busiest on the entire system. But where should it go? Four possibilities have been considered, and two — placing a station at or near the entrance to UCLA — have all but been rejected by Metro for practical reasons. The streets and sidewalks around LeConte and Westwood Boulevard are narrow, construction would be more difficult than usual, and the clincher: subway tracks that far into the village would have to pass under graves at the Los Angeles National Cemetery, and that's a cultural no-no.
So that leaves two spots along Wilshire Boulevard, either at Westwood Boulevard or under UCLA's Lot 36 at Veteran Avenue. Either of these would require major disruption at one of the city's most heavily traveled intersections, and would leave riders quite a ways from the UCLA campus or the hospital. But they also have built-in pluses. At Metro's blog The Source, Steve Hymon ticks off the issues in an impressive run of 14 digestible bullet points.
By the way, he also asked readers for their preference — and so far Wilshire at Westwood gets half the votes. Prediction: Lot 36 will get the nod, for all the logical reasons Hymon gives. Disclaimer: I work for UCLA but couldn't speak for them on this if I wanted to, which I don't.