I don't think China will make a grab for Taiwan until just after they host the 2008 Olympics. After that, it seems likely (probably just after GWB leaves office in 2009).
If China has intentions on Taiwan I just dont' see how that helps them at all. But they do like to saber rattle and throw the monkey wrench into our plans for a more peaceful world. Just their way and we'd do well not to forget that.