I have noticed this as well - my iPhone seems to be reporting much better signal strengths today, after 2 restarts.
A number of users are reporting that iPhone software/firmware 1.1.4 does indeed provide a healthy boost in cell signal strength, which was severely degraded for some users under the 1.1.3 software/firmware revision (prompting a series of boosting methods including one that involves scotch tape). This enhancement stands in addition to a series of other undocumented fixes in 1.1.4. [From iPhone 1.1.4 boosts cell signal strength]