NEW YORK ( TheStreet) -Whitney Tilson, the founder and managing partner of T2 Partners LLC and the Tilson Mutual Funds, recently wrote a detailed thesis on Seeking Alpha that Netflix's ( NFLX) (NADAQ:NFLX) stock presents an exceptional short opportunity.In response to this, Netflix's CEO Reed Hastings countered with his own commentary dissecting Whitney's analysis and asserting a growth outlook for his company. While the discussion emphasized margins in the years ahead, we believe that the prospect of subscriber saturation represents a more substantial long-term risk to Netflix's growth. As we examine Netflix's subscriber growth prospects in the face of market saturation, we pose the following hypothesis. Arguing for Netflix stock upside is equivalent to betting that Netflix (approaching 20 million subscribers) can close in on the number of subscribers that AT&T ( T) or Verizon ( VZ) garners in the mobile phone market (near 100 million subscribers). Our current price estimate for Netflix's stock stands at $106, which is significantly below the current market price. Netflix's subscriber has grown rapidly over the past few years, from a mere 4.2 million in 2005 to a robust 19 million (est.) at 2010 year-end. We anticipate continued growth of Netflix's subscriber base driven by increased adoption of its by-mail DVD business model and video streaming offerings, and project that total users will breach 40 million by the end of our forecast period on the strength of international expansion. Thus, our analysis already incorporates an optimistic subscriber growth scenario.