Hi All,
After playing the addictive Facebook "Bejeweled Blitz" game, I have some observations that can help you get the multipliers faster and increase your scores.
The “good,” “excellent,” “incredible” comments while you’re playing are misleading. You’d think that they should make those multiplier gems fall, but they don’t necessarily, so it can be confusing.
The way to get the multiplier gems is to make a move that causes a resulting match to explode a power gem, or make a move that makes at least a 3-cascade move afterward, because it’s a combination of speed and increased points due to higher point cascade matches that bring the multiplier gems into play. (I’ve included some examples!)
So… if you see a power gem, look for a move that you can make that will make the power gem match the second one in the same move.
Here are three pictures...

Don’t explode the green power gem and then the red one, because they won’t create a higher point match for the red one. You’d want to explode the red one which will cause the green one to explode with a higher point score.

If you make a green gem match by moving the arrowed gem to the left, the red gem will fall and make power gem match as the second one in the cascade and probably cause a multiplier gem to drop.

Move the blue gem up to make a blue gem match, then your second match in the cascade will be a power gem.
It’s hard to keep an eye on these but if you train yourself not to automatically match the power gem without looking for a move that will cause the power gem to match second, then your scores should improve.
Once you have a multiplier gem, try to match it as soon as possible, but don’t get caught up in matching it for too long. If you make more matches like the ones I’ve shown you, then other 2X gems will fall, and as soon as you match one 2X, the other one will become 3X. etc.
And interestingly enough, using a hypercube doesn’t always make a multiple-X gem fall, but I usually use them quickly anyway to make other moves show up, and I use them on the color that has the most gems on the screen.
And the last clue... don't watch the scores - just play. When your eyes go to the score, then you're taking seconds away from your play.
Happy Gem Matching!
Julia G