Wolfgang's Vault is an online archive containing hundreds of high-quality concert recordings, mostly from big classic-rock artists like The Who and U2, but with a few newer artists, such as The Walkmen, thrown in as well. (Here's a complete list of performers whose recordings are available on the service.)
The update adds a couple minor features, including a list of featured concerts--helpful for keeping track of shows that have been recently added to the vault--and fixes some reported problems with stuttering and stalling.
I've been listening to the Who's 1973 performances of "Quadrophenia" over a 3G connection for the last half hour, and so far, the app--and the band--are both performing flawlessly. This is a worthy update to a must-have download for live music fans.