Yes! I remember posting in your thread about it. I loved it. It was refreshing to see an indy film that wasn't so dark and depressing, and instead cheerful and optimistic.
Also, just last weekend I watch Josh Rador's (the writer/director of Happythankyoumoreplease and star of HIMYM) newest film called Liberal Arts. It's every bit as good and upbeat as his predecessor. The ending was a little rushed and convenient, but like I said, I support a top notch American indy film actually leaving on a happy note rather than a depressing one since it's so rare these days.
I've heard Liberal Arts is good, but a step down from Happythankyou. I'll probably check it out if the opportunity is presented to me.
Have you seen Win Win? It's not quite as indy-status as Happythankyou or Liberal Arts and its cast is a bet better known (Paul Giamatti stars and Amy Ryan plays his wife), but it's another generally uplifting movie with a happy ending.
And if you're not opposed to doing a little searching, there's a great indy film out of New Zealand called Boy. It was probably my favorite thing I saw at Sundance when I went besides Happythankyou and maybe Splice. Here's the IMDb page: http://www.imdb.com/title/tt1560139/?ref_=fn_al_tt_1