Are you growing them in a different place from previous years, or have you changed what you feed them this year? Plants often get tall before flowering if light levels are poor, but usually look a bit thin as well - equally, high nitrogen feed will cause more leaf and stem growth. Either that or they're not the variety you think they are...

Some of the beefsteak varieties will do that but they look all 'in proportion' with a nice sturdy stem etc. If you grew them from seed and were a bit late getting them out due to weather etc then they might have become a bit leggy.