The middle of earnings season was a mixed bag, but the bookends were really solid. Novartis (NYSE: NVS) kicked things off well a few weeks ago and Pfizer (NYSE: PFE) rounded off the season with a solid showing today.

Here's a sign of just how good things were for Pfizer: Lipitor sales actually increased 5% year over year. I'm not sure investors have seen an increase in sales of the top-selling drug since Merck's (NYSE: MRK) Zocor went generic a few years ago and AstraZeneca (NYSE: AZN) made a strong push with its newer statin, Crestor. The increase was entirely due to currency changes, however; sales were flat at constant currencies. Still, flat is better than declining any day.

Pfizer had some other solid showings as well. Sales of Lyrica were up 19% at constant currencies and Wyeth's products, such as the new version of the childhood vaccine Prevnar and Enbrel, which it sells outside the U.S. and Canada for Amgen (Nasdaq: AMGN), also contributed to the second quarter's solid revenue.

Add in cost savings from the Wyeth acquisition, and Pfizer registered adjusted earnings of $0.62 per share, a 29% increase year over year. That number subtracts out costs associated with the acquisition and integration of Wyeth. So far, Pfizer is making the acquisition work.

The future, on the other hand, is a big mystery. Pfizer expects adjusted EPS between $2.25 and $2.35 in 2012, the year after Lipitor starts to see generic competition. That's higher than the adjusted EPS it's guiding for this year. In order to hit its target, Pfizer needs some positive results from its pipeline.

There's a lot of pessimism built into Pfizer's shares, which can work in investors' favor, as you can see from the 5% increase today. But be careful; Pfizer isn't out of the woods yet. The long-term effect on integration, site closures, and layoffs is yet to be seen.