Here are a few recent literature citations regarding the issue of gluten sensitivity (all 2012). It's obviously an issue in flux, so these aren't meant to be definitive. But the topic has legs and we'll have more answers as time marches on.
http://www.ncbi.nlm.nih.gov/pubmed/22149581
Title: "Gluten sensitivity: problems of an emerging condition separate from celiac disease"
"Gluten sensitivity appears to be emerging as a separate condition from celiac disease, yet
no clear definition or diagnosis exists. As a result, patients with gluten sensitivity experience delayed diagnosis and continuing symptoms if they consume gluten."
http://www.ncbi.nlm.nih.gov/pubmed/22371218
Title: "New understanding of gluten sensitivity"
"Among gluten-related disorders, gluten sensitivity is an emerging entity that is characterized by a wide array of manifestations."
"Symptoms improve or disappear when gluten is withdrawn from the diet, and recur if gluten is reintroduced. Laboratory tests are usually unhelpful for diagnosis..."
"
Further research is necessary to establish the main clinicopathological features of gluten sensitivity, thus enabling physicians to improve their management of the increasing number of patients who are sensitive to dietary gluten."
http://www.ncbi.nlm.nih.gov/pubmed/22237879
Title: "Celiac disease, wheat allergy, and gluten sensitivity: when gluten free is not a fad."
"Gluten sensitivity is a controversial subject, where patients who have neither CD nor wheat allergy have varying degrees of symptomatic improvement on the GFD."
"Defining the symptoms and biochemical markers for gluten-sensitive conditions is an important area for future investigations, and
high-quality, large-scale randomized trials are needed to prove the true benefits of the GFD in this evolving field."
http://www.ncbi.nlm.nih.gov/pubmed/22313950
Title: "Spectrum of gluten-related disorders: consensus on new nomenclature and classification."
"Now we are observing another interesting phenomenon that is generating great confusion among health care professionals. The number of individuals embracing a gluten-free diet (GFD) appears much higher than the projected number of celiac disease patients"
"This
trend is supported by the notion that, along with celiac disease, other conditions related to the ingestion of gluten have emerged as health care concerns. "
" This review will summarize our current knowledge about the three main forms of gluten reactions: allergic (wheat allergy), autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia) and possibly immune-mediated (gluten sensitivity)..."
http://www.ncbi.nlm.nih.gov/pubmed/22351716
Title: "Nonceliac gluten sensitivity: sense or sensibility?"
"Recent studies support the existence of a new condition, nonceliac gluten sensitivity, which manifests as intestinal or extraintestinal symptoms that improve or disappear after gluten withdrawal in individuals with normal small-bowel mucosa and negative results on serum antitransglutaminase and antiendomysial antibody testing."