From that article i linked to:
A often mentioned disadvantage of flash-based storage is the limited number of write cycles (typically 100,000 for the current generation Single-Level Cell (SLC) NAND, the type usually used in the faster CF cards). This should not however be as much of an issue because...
• The 100,000 write cycles applies to each address block separately in the card, not to the card as a whole
• The flash controller automatically distribute write operations evenly (wear leveling), so that the number of writes to each address block is kept low
Therefore, it should take years of typical real world usage to render a current flash memory card based on SLC NAND unusable