April showers have come and gone, and now we're blooming in May.

Eye the calendar and you will find some meaty corporate events that may very well shape the market. Here are a few of the days that I plan to approach with eyes wide open.

May 3
Shares of Sirius XM Radio (Nasdaq: SIRI) hit new highs last week. Now it's time to earn them.

The satellite radio operator posts its first-quarter results tomorrow morning. Wall Street's looking for modest growth and another profitable quarter. Investors will have other questions in mind.

  • How many net subscribers were added during the first three months of the year?
  • Are more accounts paying for premium online streaming now that Howard Stern is available through the Sirius smartphone app?
  • Churn and conversion rates have been improving in recent periods. Are the positive trends continuing?

May 11
Cisco
(Nasdaq: CSCO) has taken a beating, and deservedly so. The networking gear giant that a decade ago commanded the country's largest market cap for a brief time is in trouble, and we'll see its latest update May 11.

Investors that bought into Cisco under the assumption that it would thrive in an economic recovery as companies ramp up their IT budgets messed up. Cisco isn't the bellwether it used to be. Competition is fierce, and analysts actually see Cisco's profitability declining this year.

These aren't merry times. Cisco is restructuring consumer-facing divisions and egging on elder hires to consider early retirement in a cost-saving move. In short, it's going to be a lively conference call.

May 12
A merrier tech stock -- NVIDIA (Nasdaq: NVDA) -- reports a day after Cisco. The video chip pioneer has managed to remain relevant as a key player in new forms of portable computing.

NVIDIA's just hitting its stride these days. The pros are banking on a 57% spike in profitability this fiscal year, a welcome contrast to Cisco's struggles.

May 15
We will see a wee Wii price come May 15 if the blogosphere is to be trusted. A trusted yet unnamed source is telling tech blog Engadget that Nintendo (OTC BB: NTDOY.PK) will be slashing the price of its signature console from $200 to $150.

The rumor makes sense. May 15 is a Sunday, the day promotional circulars touting new sales populate the morning newspaper. Nintendo also went on to announce that its Wii successor will hit the market next year, so marking down the original makes tactical sense to keep sales coming between now and then.

Nintendo will have plenty of catching up to do with Wii 2. The original was popular despite packing a weaker spec sheet than its rivals, but Xbox 360 and PS3 have gone on to match Wii's motion-based controller that was a key differentiator a couple of years ago.

May 17
Where have all the PC heroes gone? Dell (Nasdaq: DELL) reports on May 17. Rival Hewlett-Packard (NYSE: HPQ) checks in the following day.

Both companies have fallen out of favor lately. Fears that smartphones and tablets will eat into sales of their desktops and laptops have kept enthusiasm in check. Dell and HP aren't exactly throwing in the towel. HP acquired Palm last year. Both Dell and HP have expanded into higher-margin service areas. Dell and HP have also spent the past couple of years dramatically shaving their overhead. The effort is there but can the same be said for marketplace relevancy?

May 23
Vertex Pharmaceuticals
(Nasdaq: VRTX) investors have been circling this date for weeks. The Food and Drug Administration has set May 23 as the date by which it should decide on whether to approve Vertex's promising hepatitis C drug for sale in this country.

With an estimated 3 million people inflicted with the chronic liver infection in the U.S., a regulatory nod of the head or a shake will move Vertex shares. The FDA is likely to either clear or block the drug's sale before May 23, but that is the regulator's deadline.

What are you looking forward to this month? Check in with your expectations in the comment box below.

Vertex Pharmaceuticals is a Motley Fool Rule Breakers selection. Nintendo and NVIDIA are Motley Fool Stock Advisor picks. The Fool has created a bull call spread position on Cisco Systems. Motley Fool Options has recommended writing puts on NVIDIA. Alpha Newsletter Account, LLC owns shares of Cisco Systems. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.  

Longtime Fool contributor Rick Munarriz thinks that every month is special in its own way. He does not own shares in any of the stocks in this story. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.