Here is a look at some of the transportation headlines gathered by us and the Metro Library. The full list of headlines is posted on the Library’s Headlines blog, which you can also access via email subscription or RSS feed.

U.S. report backs high-speed rail revenue and ridership numbers (L.A. Times) 

The General Accounting Office says that numbers included in the California High-Speed Rail Authority’s business plan for the bullet train are realistic, although they have drawn considerable criticism from some politicians who aim to derail the project. The GAO says the biggest challenge for the project is coming up with the $51 billion combined it will need from the federal government and private interests; the overall cost to connect San Francisco and Los Angeles is currently estimated at about $68 billion.

Worst traffic gridlock in 18 years in Santa Monica? (Santa Monica Dispatch)

One woman thinks the congestion in downtown SaMo has never been worse than it was on a recent Saturday — with the construction of the Expo Line on Colorado Avenue apparently not helping. Commenters feel otherwise, saying it doesn’t help when people such as the writer of this piece insist on driving a few blocks instead of walking or taking transit.

Compare the urban density of U.S. urban areas (Greater Greater Washington) 

Cool breakdown of urban areas. Only four cities in the country have peak densities of more than 100,000 people per square mile — New York, Chicago, Boston and San Francisco. Los Angeles’ density tops out at 94,000 per square mile, mostly in the central city area. That’s very dense compared to many large cities. Check out the maps. Peak density is different than overall density of the region; the L.A. region is pretty dense by both measures, not to mention it’s overall population.