The 'more interesting' look of the menubar was, to say the least, distracting when working day-to-day with Tiger. The new look is more toned down and 'better' in this regard. Those new look things, btw., wear off quickly once you're actually using new systems. So they have to be compatible with everyday use, and the Bright blue background of earlier Apple and Spotlight logos in past builds were MUCH too distracting...
But I think Apple will try out several new looks until Final (they've already changed things there a couple times by now in Tiger betas), and I hope it'll be _slightly_ changed from how it is now - the blues and grays don't yet seem to match the general look completely yet.
Btw.: It looks like the only thing that was kept through these changes is that the menu bar will _really_ adopt the two-tone look from other UI elements already present in Panther (for example the buttons on Safari). And I like that very much. Non-intrusive, but much better than the lines in Aqua (Jaguar and earlier) and toned-down Aqua (Panther).