A trip today for a preliminary press event. Good news and bad news.
Good news: transportation! Only 20 minutes via the new subway Line 10 from Guomao station, in the central business district, to Beitucheng station, just south of the main Olympic areas. Line 10 train was populated but not overcrowded. Security check on way into the subway reasonable-seeming rather than too intrusive. (Handbags and briefcases go through a screening machine; people themselves don't have to.)
In theory there is a way to connect at Beitucheng from Line 10 to the new Olympic Line 8. But the cops seemed to be steering anyone without a formal Olympic credential (which I don't have) away from Line 8 and out onto the street. No problem: A few minutes' walk away was a depot for various special Olympic bus lines that circle the venues. The bus-route maps I saw were written only in Chinese -- or sometimes transliterated into Roman characters in a way most visitors wouldn't recognize. (For instance, Guojia Tiyuchang, the pinyin version of 国家体育场, rather than the more useful-to-outsiders terms "National Stadium" or "Bird's Nest.") But there were many cheery young English-speaking volunteers willing to help puzzled foreigners.