While touring, McMahon suffered from writer's block, which did not dissipate until mid-2006; many of the songs that would appear on The Glass Passenger were written mid-to-late 2007.

Most of the recording was done by December 2007, but label and business problems started to creep into the sessions, resulting in McMahon going on a sabbatical in January 2008.

Musically a power pop album, with comparisons to Ben Folds and Bruce Hornsby, The Glass Passenger saw McMahon focus on the aftermath and the recovery from his leukemia, backed with a new-found perspective on the world.

The album received a positive reception from critics, with a few commenting on lyrics and the record serving as a good follow-up, or even besting, Everything in Transit.

[5] Around this time, he was working on Treaty of Paris' debut album Sweet Dreams, Sucker for his label Airport Tapes and Records.

[7] He said the material was specifically intended for the next Jack's Mannequin record and was reminiscent of the Postal Service and Beck's Sea Change (2002).

[7] With the touring cycle for Everything in Transit finishing in March 2007, McMahon focused on writing new material, though he was unsure if it would be for Jack's Mannequin or his other band Something Corporate.

[9] McMahon wanted to make a "very organic" and "natural-sounding" album that stood apart from a few of the "more digital approaches" used when recording music.

[10] These sessions marked the first time McMahon worked in the studio with his backing band, which consisted of Anderson, bassist Jon Sullivan and drummer Jay McMillan.

[4] Wanting to have the album "feel played", as opposed to "chopped up and doctored", a lot of ideas were shared among everyone in the studio—six or seven people at any given time.

[15] He wanted to avoid writing "the cancer record" as he described it, preferring instead to tackle other themes that had cropped up in his life—the most common being able to find "light in the struggle [of getting through life]".

[4] Musically, the album's sound has been classed as power pop,[18] with comparisons being made to Ben Folds,[19] and McMahon's piano playing being described as reminiscent of Bruce Hornsby.

[22] "Suicide Blonde" features new wave-style guitar parts,[27] alongside McMahon, Wirt and Anderson playing kazoos, and Sullivan using a talk box.

[35] During July, McMahon told the Montclair State University student newspaper the release date would be moved to late August or early September 2008.

[44] Meyer then re-watched music videos she loved to get a sense of style, including those for OK Go's "Here It Goes Again", Brand New's "Sic Transit Gloria...

[52] McMahon explained that while making "Miss California" he was not that impressed with it, but by the time it came to be mixed he highly enjoyed it, and included it as bonus track to not disrupt the sequencing.

[51] The collectors edition CD/DVD combo includes a short film Choke, California, directed by James Minchin III.

[66] In October and November, the band went on a club tour in the US titled Hammers and Strings: An Evening with Jack's Mannequin and The Glass Passenger.

[69] Dubbed the Father from the Earth tour, the band was supported by Matt Nathanson, Low vs Diamond and Erin McCarley.

[77] Though he mentioned it might not "seem as initially compelling" as Transit, the "glorious" melodies were clear evidence that the band surpassed the sophomore slump "with flying colours".

[77] Annie Zaleski of Alternative Press noted that it was considerably "more complex and sophisticated" than Transit, writing that a person does not need to know McMahon's life story to "relate to and resonate with his music", which in turn makes it "a fantastic, special album".

[27] AbsolutePunk staff member Drew Beringer said the album's "variety and diversity" removes it from Everything in Transit and other pop releases.

[23] He felt that both McMahon's lyrics and song structures "continue to get better" as he "cement[s] himself as the current scene’s best pop musician".

[23] Sputnikmusic emeritus Athom wrote that the majority of the tracks, despite being rooted in "typical pop-rock like broken hearts and separation", managed to pull off "as surprisingly personal".

[79] Entertainment Weekly's Jaya Saxena found the lyrics "often revealing" as McMahon comes across as "a bit bored" with him "forc[ing] clichéd metaphors into power ballads".

[76] Making it two-thirds into the album to "the genuinely heartfelt 'Hammers and Strings (A Lullaby)'", it's "too late; the ratio of cheese to sincerity is just too high".

[76] AllMusic reviewer Andrew Leahey wrote the album's introspective narrative "sometimes pales in comparison with the summery songs" featured on Transit.

[22] He added it may not contain pop hooks like those on Transit, but it "does stay afloat under the weight of McMahon's past, which bodes well for the songwriter's future work".

[22] PopMatters editor Evan Sawdey referred to the album as a "half-baked collection" of tracks which "lose sight" of McMahon's strengths to focus more so on a "grandiose sense of self-importance".

[78] Spin writer Jon Young said the album "match[es] hyperemotional melodies" with McMahon's "tender voice on dramatic tracks".