"Some Respite, prithee do, yet do not give,
I cannot with thee, nor without thee live."

-- From "VI Mon. August [1742] hath xxxi days", by Benjamin Franklin

Research In Motion (Nasdaq: RIMM) must know what Benjamin was talking about in this ode to mixed feelings. Mr. Market expects the moon from the company every quarter, and merely great results are never good enough.

The BlackBerry maker reported 18% year-over-year sales growth and 41% earnings-per-share growth for the fourth quarter, landing at $4.1 billion and $1.27 per share, respectively. These are improvements that would do high-growth fixtures like Apple (Nasdaq: AAPL) or Google (Nasdaq: GOOG) proud, and yet Research In Motion's stock is down 6% on the news.

In all fairness, Research In Motion tied its own noose this time. Sales fell short of management guidance, though a strong gross margin kept earnings within the expected range. Low-priced models like the BlackBerry Curve accounted for much of RIM's revenue, which led to soft top-line dollars -- but it looks like those phones also come with low manufacturing price tags, as the same phenomenon also was used to explain the strong margins. All of these moving parts were pushed by torrid holiday sales at retailers like Best Buy (NYSE: BBY) and RadioShack (NYSE: RSH).

Much of Research In Motion's growth comes from existing BlackBerry users upgrading their old phones to a newer model: More than half of the phones shipped in the quarter replaced existing BlackBerrys without adding new subscriber accounts. If that upgrade cycle ever ends, the company would be in deep trouble because the volume of truly new accounts is nowhere near enough to sustain the share price. And with a torrent of new smartphones coming in from Apple, the Google Android camp, Nokia (NYSE: NOK), and others, Research In Motion is fighting an uphill battle to maintain its market share.

If Research In Motion has one thing going for it, that would be its focus on international growth. Spearheaded by a new manufacturing facility in Brazil in partnership with Flextronics (Nasdaq: FLEX), that effort holds promise to keep the company growing by pushing into markets where the BlackBerry is not a big name today.

Co-CEO Jim Balsillie is drooling over the products on his road map -- but then again, it's kind of his job to work up excitement over it. Research In Motion needs a couple of home runs to stay relevant, and soon. Lather, rinse, repeat as the competition grows stronger and stronger.

Can Research In Motion survive in the new smartphone landscape? I'm not so sure, but feel free to vent your opinions in the comments below.