Don't get ahead of yourselves - Isner still has to win a 2nd-round match to get there. Now, I know it might not seem like too big a deal (especially playing a qualifier, Rik De Voest), but remember that this is just his first Grand Slam - he'll be the favorite in the match, but winning it isn't a done deal.
It would be great for him to even get to the third round - yeah, he'll get beaten down by Federer, but really, so what? So's everybody else in Fed's path. He's living his dream and he's got a great game.