alt Hacker NewsMy credit union gives me better rates if I'm "active", which means some number of transactions per month. Thus you really need to pick a credit union and start using them a few months before if you want the best rates. (maybe, depending on how that credit union works)
Yeah, there's a somewhat wide variance in CUs, in terms of rates, quality of service, etc. I called a few just to spot check and these public rates are supposedly about as good as they can do. From what I gather, even the large CUs (like Transportation FCU) just don't have that sophisticated of an operating model.