What's missing in Lotro-wiki? It seems to be covering all the changes with Isengard though I haven't check the numbers. It's not a "guide" though, you have to figure out on your own what's a good way to use the skills.
What information are you looking for on lotro-wiki that's not there? I did a big update after RoI and some little ones for the few things that changed with Update 6. I admit I haven't completely cross-linked all the interactions between traits and skills and legacies, but as far as I know the Minstrel information that's there is all current. If you disagree, I would like to know so I can fix it up.
Just to echo what's already been said here, that Lotro-wiki seems pretty current to me although there's the odd result (or lack of one) that pops up from time to time. It's still, to my mind, the best reference material out there. It isn't a guide though, it's an information resource; for the best guide to playing a Minstrel on the whole of the internets then Cloudie-Wan's guide (linked above) is the place to look.
Ah yes, that's because the main Minstrel page does not actually have much on it directly, so the updates wouldn't show up there. Instead it's more of a summary that pulls from other pages, so the info only has to be entered once and not manually copied everywhere it's needed. If you look at the history for http://lotro-wiki.com/index.php/Minstrel_Skills for example, or at any of the individual skill or trait pages, you'll see the relevant edit history.