The tech earnings picture continues to look decidedly mixed. Last week, chip maker AMD came out with awful results, while its rival Intel managed to report decent earnings, even as it acknowledged that a price war was causing it some pain. Last night, one of the ultimate tech bellwethers, IBM, released its quarterly results, and while the initial numbers looked good, some see cause for concern. Because IBM is so diversified across multiple business lines and has such a broad customer base, its results are a pretty good proxy for tech spending as a whole. Although the company's earnings gained, it said that its US business actually shrank amidst an overall slowdown in tech spending by enterprise customers. This is a pretty ominous sign for a number of companies that are dependent on corporate spending for most of their revenue, so it'll be interesting to see whether this softness continues to be reflected in more of their earnings.