Yes, they have been doing an excellent job. I've donated to them more than once because I find myself using the IA on a nigh-daily basis.

But the IA is no panacea. It can only store some categories of content reliably, and the rest is inaccessible. Nor have I seen them hold & distribute the truly enormous datasets that much research will use - the biggest files I've seen the IA offer for public download are in the single gigabytes or hundreds of megabytes range.