To exactly know how many years more Salesforce will be active then you need to regularly check the customers increasing or decreasing Year by Year. If the demand for salesforce services are increasing then definitely I will say that salesforce and their employees future is bright : )
In 2016 salesforce appoints 100, 000 + jobs in the Salesforce market and increases the number of jobs year by year. Salesforce call that still 60% of business is going to the cloud in the next 5-10 years that creates added livelihood opportunities for the Salesforce Developers.
It is my suggestion that if any student would like to enter into the salesforce job market then this is the best time to start learning and exploring new things. Currently Salesforce job market has less competition and if you come along with programming background then its fantastic path for you to grow.
Don’t worry if you are not from programming background because there are other jobs also available where no need for programming required like salesforce marketing and many more who gives equal opportunities to Programmers and Functional experts.