Is there a max allowance for entries in a table in mysql?
I took a look at MySQL documentation and there seems to be no maximum number for records in a table, but taking a look at MySQL features page:


  Scalability and Limits:
  
  Support for large databases. We use MySQL Server with databases that
  contain 50 million records. We also know of users who use MySQL Server
  with 200,000 tables and about 5,000,000,000 rows. 
  
  Support for up to 64 indexes per table (32 before MySQL 4.1.2). Each
  index may consist of 1 to 16 columns or parts of columns. The maximum
  index width is 1000 bytes (767 for InnoDB); before MySQL 4.1.2, the
  limit is 500 bytes. An index may use a prefix of a column for CHAR,
  VARCHAR, BLOB, or TEXT column types.


According to this information, the recommended maximum number of records may vary a lot depending on your hardware limitations but would probably be around the boundaries of 5,000,000,000 rows.

EXTRA: if you plan to store really large numbers of records in a table, care to use the MAX_ROWS parameter in your CREATE TABLE data definition statements.