The American Association of Individual Investors Sentiment Survey reflects an increase in bullish sentiment as of 4.11.2007. Bullishness increased to 40.85% from last week's 32.26%.
Laszlo Birinyi's Tickersense site also maintains a Ticker Sense Blogger Sentiment Poll. His poll surveys the web's most prominent investment bloggers, asking "What is your outlook on the S&P 500 for the next 30 days?" His poll (with chart) shows bullishness has been on the increase since mid-March.