The SSD alone would be an absolutely stupid idea to upgrade. If you really needed some extra processing power with the SB chips or if you really needed a better display, then maybe it would be worth an upgrade. But spending 500-600 to upgrade only one generation just doesn't seem worth it to me.
To put things in perspective, if you want the SSD, you can get a 240 GB SSD from OWC that will no doubt be faster than Apple's drives for $520. Apple currently charges $650 for that price. Now, the cost of SSDs might come down with the generation update, but at worst, you still just break even in terms of money, and you lose a lot of time and effort.