Having seen all 3 of the movies mentioned, I did not think this was a rip off of those films. In fact, I didn't even think of Zac Braff until this post.
Looks like you left your comment before the film even came out, so maybe next time you should wait until you've watched the film before saying it's a rip off?
http://mopedjonesindiemusic.tumblr.com/

Much debate on how many stories. I guess it depends on how you define the situation.
http://www.theguardian.com/notesandqueries/query/0,,-1553,00.html
Thanks for the Polti info.

FYI
Polti wrote "The 36 Dramatic Situations" in the 19th Century. According to his research, these were the only possible variations in plot, and everything is derived from those.

In literature there are only 3 stories . . . all repeated over and over and over again with slightly different interchangable parts. Get used to repetition in the arts.

AH. tell Radnor he's ripping off a Jersey movie and he'll probably give you a 4 hours lecture on all the differences between the two.

The Last Kiss is just a horrible ripoff anyway, when compared to the movie it's based on, L'Ultimo Bacio.

But the character arcs and the motivations are completely different.
In The Last Kiss, the older guy (Zach Braff) falls for the younger girl because he wants to feel young again. He needed excitement to escape what he thought was a boring suburban life. His conflict was resolved when he realized that he preferred the intimacy and familiarity with his wife.
In Liberal Arts, the older guy (Josh Radnor) never grew out of his college personae. He fell for the younger girl because they were at the same emotional stage. She was advanced for her age, and he was stunted. His conflict was resolved when he realized that he needed to move past romanticizing that period of his life and be okay with moving into the next stage of life. He needed to be okay with the process of transforming from the caterpillar to a butterfly (to borrow the metaphor used in the film).
In other words, they really aren't similar in the way that you describe. They are completely different arcs with completely different messages.

He's aiming more towards a Woody Allen style, but I can see how people think he's just taking from Garden Statethis and Garden State are pretty surface dense in comparison to the never ending barrel depth found in even the most accessible Woody Allen film.

Well, it does fit in with the older guy in a midlife crisis falling for a younger girl syndrome. In that way they are very similiar.

The only comparison between the two is that they were written/directed/starring actors who were leads of successful sitcoms. Plot wise they aren't alike.

I didn't think Happythankyoumoreplease was like Garden State at all. Examples, please.