I've unfortunately made two changes making it hard to figure out which is causing this, but I suspect the problem is Lion. Since upgrading to Lion (and with a new MacBook Pro), I have found Wifi at airports unusable. These are Wifi networks supported by, e.g., ATT, Boingo, or airports generally — basically any wifi network where you need to log in to get access (as opposed to give a key). The new fancy automatic detection system is INCREDIBLY slow. Yesterday, it took me 20 minutes before the system would connect (even through I was in areas with maximum bars coverage).
Is there someway to downgrade the code that's being used? The machine has become essentially useless when traveling (3G on my phone is better).