Having a hard time keeping the market share %’s (between Google, Yahoo, MSN, and others) straight? So are we. As with many things in this industry, the answer to the question depends on who you ask.

Efficient Frontier analyzed their own client data, and has recently published Q4 2007 US Search spend share %’s

• Google: 76.6%
• Yahoo: 17.9%
• MSN: <5.5%

see the rest of the story here.

HitWise also recently published their December 2007 US Search numbers:

• Google: 65.98%
• Yahoo: 20.88%
• MSN: 7.04%
• Ask.com: 4.14%
• Remaining 49 engines: 1.96%

See the full report here.

Also, from a previous post, Nielsen Online shows the US Search Market as:

• Google: 56.3%
• Yahoo: 17.7%
• MSFT: 13.8%
• Others: 12.2%